diff --git a/custompages/first_login.php b/custompages/first_login.php
index 6f3c6b512d..35c851a4f1 100644
--- a/custompages/first_login.php
+++ b/custompages/first_login.php
@@ -7,9 +7,9 @@
 /**
  * Initialization
  */
-require_once('language.php');
-require_once(dirname(__FILE__).'/../main/inc/global.inc.php');
-require_once (api_get_path(LIBRARY_PATH).'usermanager.lib.php');
+require_once 'language.php';
+require_once dirname(__FILE__).'/../main/inc/global.inc.php';
+
 /**
  * Security checks
  */
@@ -17,8 +17,8 @@ if (! isset($_SESSION['conditional_login']['uid']))
   die("Not Authorised");
 
 if (isset($_POST['password'])){
-  $u = UserManager::get_user_info_by_id($_SESSION['conditional_login']['uid']);
-  if ($_POST['password'] != $_POST['password2']) { 
+  $u = UserManager::get_user_info_by_id($_SESdiagnoser.lib.phpSION['conditional_login']['uid']);
+  if ($_POST['password'] != $_POST['password2']) {
     header('Location: '. api_get_self().'?invalid=2');
     exit();
   }
@@ -59,11 +59,11 @@ if ($_GET['invalid'] == 2) {
 	<script type="text/javascript" src="/main/inc/lib/javascript/jquery.min.js"></script>
 	<script type="text/javascript">
 		$(document).ready(function() {
-			if (top.location != location) 
+			if (top.location != location)
 				top.location.href = document.location.href ;
 
 			// Handler pour la touche retour
-			$('input').keyup(function(e) { 
+			$('input').keyup(function(e) {
 				if (e.keyCode == 13) {
 					$('#changepassword-form').submit();
 				}
@@ -80,12 +80,12 @@ if ($_GET['invalid'] == 2) {
 			<img src="/custompages/images/header.png" alt="Logo" />
 		</div> <!-- #header -->
     <h2> <?php echo custompages_get_lang('FirstLogin');?> </h2>
-        
+
 		<div id="changepassword-form-box" class="form-box">
       <div class="info"> <?php echo custompages_get_lang('FirstLoginChangePassword');?> </div>
 		<?php if (isset($error_message)) {
 			echo '<div id="changepassword-form-error" class="form-error">'.$error_message.'</div>';
-		}?> 
+		}?>
 			<form id="changepassword-form" class="form" method="post">
 				<div>
           <label for="password">*<?php echo custompages_get_lang('langPass');?></label>
diff --git a/main/admin/settings.lib.php b/main/admin/settings.lib.php
index 48ecf05d29..333e78b296 100644
--- a/main/admin/settings.lib.php
+++ b/main/admin/settings.lib.php
@@ -604,8 +604,7 @@ function handle_search() {
     echo '</div>';
 
     if ($search_enabled == 'true') {
-        require_once api_get_path(LIBRARY_PATH).'sortable_table.class.php';
-        $xapian_path = api_get_path(SYS_PATH).'searchdb';
+        $xapian_path = api_get_path(SYS_DATA_PATH).'searchdb';
 
         /*
         @todo Test the Xapian connection
diff --git a/main/admin/system_status.php b/main/admin/system_status.php
index b150e2d90d..eedc401a03 100644
--- a/main/admin/system_status.php
+++ b/main/admin/system_status.php
@@ -10,7 +10,6 @@ $language_file = array('admin', 'registration');
 $cidReset = true;
 
 require_once '../inc/global.inc.php';
-require_once api_get_path(LIBRARY_PATH).'diagnoser.lib.php';
 
 $this_section = SECTION_PLATFORM_ADMIN;
 // User permissions
diff --git a/main/blog/blog_admin.php b/main/blog/blog_admin.php
index 02696dfc95..89459f0a32 100644
--- a/main/blog/blog_admin.php
+++ b/main/blog/blog_admin.php
@@ -27,8 +27,7 @@ if((!$is_allowed_in_course || !$is_courseMember) && !api_is_allowed_to_edit()) {
 	api_not_allowed(true);//print headers/footers
 }
 
-if (api_is_allowed_to_edit()) { 
-	require_once api_get_path(LIBRARY_PATH) . "blog.lib.php";
+if (api_is_allowed_to_edit()) {
 	$nameTools = get_lang("blog_management");
 
 	// showing the header if we are not in the learning path, if we are in
@@ -49,8 +48,8 @@ if (api_is_allowed_to_edit()) {
 		'name' => $current_section
 		);
 		Display::display_header('');
-	} else {		
-	}	
+	} else {
+	}
 	echo '<div class="actions">';
 	echo "<a href='".api_get_self()."?".api_get_cidreq()."&action=add'>",Display::return_icon('new_blog.png',get_lang('AddBlog'),'',ICON_SIZE_MEDIUM)."</a>";
 	echo '</div>';
@@ -83,7 +82,7 @@ if (api_is_allowed_to_edit()) {
 		Display::display_confirmation_message(get_lang('BlogDeleted'));
 	}
 
-	/*	
+	/*
 		DISPLAY
 	*/
 	//api_display_tool_title($nameTools);
diff --git a/main/course_progress/thematic_controller.php b/main/course_progress/thematic_controller.php
index e1a610d5b6..e375ae152d 100644
--- a/main/course_progress/thematic_controller.php
+++ b/main/course_progress/thematic_controller.php
@@ -4,9 +4,9 @@
 
 /**
  * This file contains class used like controller for thematic, it should be included inside a dispatcher file (e.g: index.php)
- * 
+ *
  * !!! WARNING !!! : ALL DATES IN THIS MODULE ARE STORED IN UTC ! DO NOT CONVERT DURING THE TRANSITION FROM CHAMILO 1.8.x TO 2.0
- * 
+ *
  * @author Christian Fasanando <christian1827@gmail.com>
  * @author Julio Montoya <gugli100@gmail.com> token support improving UI
  * @package chamilo.course_progress
@@ -15,7 +15,7 @@
 /**
  * Thematic Controller script. Prepares the common background variables to give to the scripts corresponding to
  * the requested action
- * @package chamilo.course_progress 
+ * @package chamilo.course_progress
  */
 class ThematicController {
 
@@ -30,7 +30,7 @@ class ThematicController {
     /**
      * This method is used for thematic control (update, insert or listing)
      * @param 	string	Action
-     * render to thematic.php 
+     * render to thematic.php
      */
     public function thematic($action) {
         $thematic = new Thematic();
@@ -44,7 +44,7 @@ class ThematicController {
             switch ($action) {
                 case 'thematic_add':
                 case 'thematic_edit':
-                    // insert or update a thematic		
+                    // insert or update a thematic
                     if (strtoupper($_SERVER['REQUEST_METHOD']) == "POST") {
                         if (trim($_POST['title']) !== '') {
                             if (api_is_allowed_to_edit(null, true)) {
@@ -178,7 +178,7 @@ class ThematicController {
                         $data = $thematic->get_thematic_advance_by_thematic_id($theme['id']);
                         $advance_html = null;
                         if (!empty($data)) {
-                            foreach ($data as $advance) {                                
+                            foreach ($data as $advance) {
                                 $advance_html .= api_convert_and_format_date($advance['start_date'], DATE_FORMAT_LONG) . ' ('.$advance['duration'].' '.get_lang('HourShort').')<br />'.$advance['content'].'<br />';
                             }
                         }
@@ -190,7 +190,7 @@ class ThematicController {
                         'add_signatures' => true,
                         'format' => 'A4-L',
                         'orientation' => 'L'
-                    );                    
+                    );
                     Export::export_table_pdf($table, $params);
                     break;
                 case 'moveup':
@@ -214,7 +214,7 @@ class ThematicController {
             $data['thematic_id'] = $thematic_id;
         }
 
-        if ($action == 'thematic_details') {    
+        if ($action == 'thematic_details') {
             if (isset($thematic_id)) {
                 $thematic_data_result = $thematic->get_thematic_list($thematic_id);
                 if (!empty($thematic_data_result)) {
@@ -230,7 +230,7 @@ class ThematicController {
 
             //Second column
             $thematic_plan_data = $thematic->get_thematic_plan_data();
-            
+
             //Third column
             $thematic_advance_data = $thematic->get_thematic_advance_list(null, null, true);
 
@@ -256,7 +256,7 @@ class ThematicController {
     /**
      * This method is used for thematic plan control (update, insert or listing)
      * @param 	string	Action
-     * render to thematic_plan.php 
+     * render to thematic_plan.php
      */
     public function thematic_plan($action) {
         $thematic = new Thematic();
@@ -272,19 +272,19 @@ class ThematicController {
 
                             $title_list         = $_REQUEST['title'];
                             $description_list   = $_REQUEST['description'];
-                            $description_type   = $_REQUEST['description_type'];               
+                            $description_type   = $_REQUEST['description_type'];
                             $delete_list        = $_REQUEST['delete'];
-                            
+
                             foreach ($title_list as $id => $title) {
                                 $thematic_plan_id = $id;
                                 if (!$thematic->get_thematic_data_by_id($id)) {
                                     $thematic_plan_id = null;
                                 }
-                                $thematic->set_thematic_plan_attributes($_REQUEST['thematic_id'], $title, $description_list[$id], $description_type[$id], $thematic_plan_id);                                
-                                if (isset($delete_list[$id]) && !empty($delete_list[$id])) {                                    
+                                $thematic->set_thematic_plan_attributes($_REQUEST['thematic_id'], $title, $description_list[$id], $description_type[$id], $thematic_plan_id);
+                                if (isset($delete_list[$id]) && !empty($delete_list[$id])) {
                                      $thematic->thematic_plan_delete();
                                 } else {
-                                    $affected_rows = $thematic->thematic_plan_save();    
+                                    $affected_rows = $thematic->thematic_plan_save();
                                 }
                             }
                             unset($_SESSION['thematic_plan_token']);
@@ -315,11 +315,11 @@ class ThematicController {
         }
 
         $thematic_id = intval($_GET['thematic_id']);
-        
+
         if ($action == 'thematic_plan_list') {
             $data['thematic_plan_data'] = $thematic->get_thematic_plan_data($thematic_id);
         }
-        
+
         $description_type = intval($_GET['description_type']);
 
         if (!empty($thematic_id) && !empty($description_type)) {
@@ -341,7 +341,7 @@ class ThematicController {
 
         $data['thematic_id'] = $thematic_id;
         $data['action'] = $action;
-        
+
         $data['default_thematic_plan_title'] = $thematic->get_default_thematic_plan_title();
         $data['default_thematic_plan_icon'] = $thematic->get_default_thematic_plan_icon();
         $data['next_description_type'] = $thematic->get_next_description_type($thematic_id);
@@ -359,16 +359,14 @@ class ThematicController {
     /**
      * This method is used for thematic advance control (update, insert or listing)
      * @param 	string	Action
-     * render to thematic_advance.php 
+     * render to thematic_advance.php
      */
     public function thematic_advance($action) {
-        require_once api_get_path(LIBRARY_PATH).'thematic.lib.php';
-
         $thematic = new Thematic();
         $attendance = new Attendance();
         $data = array();
 
-        // get data for attendance input select		
+        // get data for attendance input select
         $attendance_list = $attendance->get_attendances_list();
         $attendance_select = array();
         $attendance_select[0] = get_lang('SelectAnAttendance');
diff --git a/main/create_course/add_course.php b/main/create_course/add_course.php
index f89d6c68c4..5b4facdf4e 100644
--- a/main/create_course/add_course.php
+++ b/main/create_course/add_course.php
@@ -32,10 +32,6 @@ $this_section = SECTION_COURSES;
 // false - the new course is created immedialely, after filling this form.
 $course_validation_feature = api_get_setting('course_validation') == 'true';
 
-if ($course_validation_feature) {
-    require_once api_get_path(LIBRARY_PATH).'course_request.lib.php';
-}
-
 $htmlHeadXtra[] = '<script>
     function setFocus(){
         $("#title").focus();
diff --git a/main/dashboard/index.php b/main/dashboard/index.php
index 09d81af1f0..600b403aae 100644
--- a/main/dashboard/index.php
+++ b/main/dashboard/index.php
@@ -1,7 +1,7 @@
 <?php
 /* For licensing terms, see /license.txt */
 /**
-* Template (front controller in MVC pattern) used for distpaching to the controllers depend on the current action  
+* Template (front controller in MVC pattern) used for distpaching to the controllers depend on the current action
 * @author Christian Fasanando <christian1827@gmail.com>
 * @package chamilo.dashboard
 */
@@ -12,10 +12,8 @@
 $language_file = array ('index', 'tracking', 'userInfo', 'admin', 'gradebook');
 $cidReset = true;
 
-// including files 
+// including files
 require_once '../inc/global.inc.php';
-require_once api_get_path(LIBRARY_PATH).'dashboard.lib.php';
-require_once api_get_path(LIBRARY_PATH).'app_view.php';
 require_once 'dashboard_controller.php';
 require_once 'block.class.php';
 
@@ -51,16 +49,16 @@ if (isset($_GET['path'])) {
 }
 
 // distpacher actions to controller
-switch ($action) {	
-	case 'listing':	
+switch ($action) {
+	case 'listing':
 		$dashboard_controller->display();
 		break;
-	case 'store_user_block':	
+	case 'store_user_block':
 		$dashboard_controller->store_user_block();
-		break;	
-	case 'disable_block':	
+		break;
+	case 'disable_block':
 		$dashboard_controller->close_user_block($path);
-		break;					
-	default :	
+		break;
+	default :
 		$dashboard_controller->display();
 }
diff --git a/main/gradebook/gradebook_flatview.php b/main/gradebook/gradebook_flatview.php
index a991a11626..44c43cf50f 100644
--- a/main/gradebook/gradebook_flatview.php
+++ b/main/gradebook/gradebook_flatview.php
@@ -23,7 +23,6 @@ require_once 'lib/fe/displaygradebook.php';
 require_once 'lib/fe/exportgradebook.php';
 require_once 'lib/scoredisplay.class.php';
 require_once api_get_path(SYS_CODE_PATH).'gradebook/lib/gradebook_functions.inc.php';
-require_once api_get_path(LIBRARY_PATH).'pdf.lib.php';
 
 api_block_anonymous_users();
 block_students();
diff --git a/main/gradebook/gradebook_showlog_eval.php b/main/gradebook/gradebook_showlog_eval.php
index f0bd53698d..496a0a2e99 100644
--- a/main/gradebook/gradebook_showlog_eval.php
+++ b/main/gradebook/gradebook_showlog_eval.php
@@ -10,7 +10,6 @@
 $language_file = 'gradebook';
 //$cidReset = true;
 require_once '../inc/global.inc.php';
-require_once api_get_path(LIBRARY_PATH).'sortable_table.class.php';
 require_once 'lib/be.inc.php';
 require_once 'lib/gradebook_functions.inc.php';
 require_once 'lib/fe/evalform.class.php';
@@ -39,15 +38,15 @@ $t_user=	 Database :: get_main_table(TABLE_MAIN_USER);
 $visible_log=Security::remove_XSS($_GET['visiblelog']);
 
 $evaledit = Evaluation :: load($visible_log);
-$sql="SELECT le.name,le.description,le.weight,le.visible,le.type,le.created_at,us.username FROM ".$t_linkeval_log." le INNER JOIN ".$t_user." us 
+$sql="SELECT le.name,le.description,le.weight,le.visible,le.type,le.created_at,us.username FROM ".$t_linkeval_log." le INNER JOIN ".$t_user." us
       ON le.user_id_log=us.user_id where id_linkeval_log=".$evaledit[0]->get_id()." and type='evaluation';";
 $result=Database::query($sql);
 $list_info=array();
 while ($row=Database::fetch_row($result)) {
-	$list_info[]=$row; 
+	$list_info[]=$row;
 }
 
-foreach($list_info as $key => $info_log) {	
+foreach($list_info as $key => $info_log) {
 	$list_info[$key][5]=($info_log[5]) ? api_convert_and_format_date($info_log[5]) : 'N/A';
 	$list_info[$key][3]=($info_log[3]==1) ? get_lang('GradebookVisible') : get_lang('GradebookInvisible');
 }
diff --git a/main/gradebook/gradebook_showlog_link.php b/main/gradebook/gradebook_showlog_link.php
index 621ac4f256..0a044bc088 100644
--- a/main/gradebook/gradebook_showlog_link.php
+++ b/main/gradebook/gradebook_showlog_link.php
@@ -10,7 +10,6 @@
 $language_file = 'gradebook';
 //$cidReset = true;
 require_once '../inc/global.inc.php';
-require_once api_get_path(LIBRARY_PATH).'sortable_table.class.php';
 require_once 'lib/be.inc.php';
 require_once 'lib/gradebook_functions.inc.php';
 require_once 'lib/fe/evalform.class.php';
diff --git a/main/gradebook/index.php b/main/gradebook/index.php
index 3c6fa0784e..c08046b8e0 100644
--- a/main/gradebook/index.php
+++ b/main/gradebook/index.php
@@ -36,8 +36,6 @@ require_once 'lib/gradebook_data_generator.class.php';
 require_once 'lib/fe/gradebooktable.class.php';
 require_once 'lib/fe/displaygradebook.php';
 require_once 'lib/fe/userform.class.php';
-require_once api_get_path(LIBRARY_PATH).'ezpdf/class.ezpdf.php';
-require_once api_get_path(LIBRARY_PATH).'gradebook.lib.php';
 
 /*
 $htmlHeadXtra[] = api_get_css(api_get_path(WEB_LIBRARY_PATH).'javascript/jqplot/jquery.jqplot.min.css');
@@ -45,7 +43,7 @@ $htmlHeadXtra[] = api_get_js('jqplot/jquery.jqplot.min.js');
 $htmlHeadXtra[] = api_get_js('jqplot/plugins/jqplot.donutRenderer.min.js');*/
 
 $htmlHeadXtra[] = '<script>
-    
+
 var show_icon = "../img/view_more_stats.gif";
 var hide_icon = "../img/view_less_stats.gif";
 
@@ -53,28 +51,28 @@ $(document).ready(function() {
 
     $(".view_children").live("click", function() {
         var id = $(this).attr("data-cat-id");
-        $(".hidden_"+id).removeClass("hidden");    
-        $(this).removeClass("view_children");        
-        $(this).find("img").attr("src", hide_icon);        
+        $(".hidden_"+id).removeClass("hidden");
+        $(this).removeClass("view_children");
+        $(this).find("img").attr("src", hide_icon);
         $(this).attr("class", "hide_children");
     });
 
-    $(".hide_children").live("click", function(event) {    
-        var id = $(this).attr("data-cat-id");        
-        $(".hidden_"+id).addClass("hidden");    
+    $(".hide_children").live("click", function(event) {
+        var id = $(this).attr("data-cat-id");
+        $(".hidden_"+id).addClass("hidden");
         $(this).removeClass("hide_children");
         $(this).addClass("view_children");
         $(this).find("img").attr("src", show_icon);
     });
- 
-    
-    
+
+
+
 
 /*
   var s1 = [["a",25]];
   var s2 = [["a", 0], ["a", 10], ["a", 10], ["a", 5]];
-     
-  var plot3 = $.jqplot("chart3", [s1, s2], {        
+
+  var plot3 = $.jqplot("chart3", [s1, s2], {
   colors: ["#000", "#fff"],
     seriesDefaults: {
       // make this a donut chart.
@@ -88,7 +86,7 @@ $(document).ready(function() {
         // By default, data labels show the percentage of the donut/pie.
         // You can show the data "value" or data "label" instead.
         dataLabels: "value"
-        
+
       }
     }
   });*/
@@ -120,7 +118,7 @@ $filter_warning_msg = true;
 
 ///direct access to one evaluation
 $cats = Category :: load(null, null, $course_code, null, null, $session_id, false); //already init
-$first_time = null; 
+$first_time = null;
 if (empty($cats)) {
 	$cats = Category :: load(0, null, $course_code, null, null, $session_id, false);//first time
 	$first_time=1;
@@ -139,8 +137,8 @@ if ( (isset($_GET['selectcat']) && $_GET['selectcat']>0) && (isset($_SESSION['st
 	//Introduction tool: student view
 	Display::display_introduction_section(TOOL_GRADEBOOK, array('ToolbarSet' => 'AssessmentsIntroduction'));
 
-	$category= $_GET['selectcat'];		
-	
+	$category= $_GET['selectcat'];
+
 	$cats = Category :: load ($category, null, null, null, null, null, false);
 	$allcat= $cats[0]->get_subcategories($stud_id, $course_code, $session_id);
 	$alleval= $cats[0]->get_evaluations($stud_id);
@@ -312,7 +310,7 @@ if (isset($_GET['deletecat'])) {
 		}
 	}
 	$confirmation_message = get_lang('CategoryDeleted');
-	$filter_confirm_msg = false;   
+	$filter_confirm_msg = false;
 }
 //parameters for evaluations
 if (isset ($_GET['visibleeval'])) {
@@ -349,8 +347,8 @@ if (isset($_GET['lockedeval'])) {
 	if ($eval[0] != null) {
 		$eval[0]->lock($type_locked);
 	}
-	
-	$filter_confirm_msg = false;	
+
+	$filter_confirm_msg = false;
 
 }
 if (isset ($_GET['deleteeval'])) {
@@ -395,11 +393,11 @@ if (isset ($_GET['deletelink'])) {
 		$link= LinkFactory :: load($get_delete_link);
 		if ($link[0] != null) {
 			// clean forum qualify
-			$sql = 'UPDATE '.$tbl_forum_thread.' SET thread_qualify_max=0,thread_weight=0,thread_title_qualify="" 
+			$sql = 'UPDATE '.$tbl_forum_thread.' SET thread_qualify_max=0,thread_weight=0,thread_title_qualify=""
 					WHERE c_id = '.$course_id.' AND thread_id = (SELECT ref_id FROM '.$tbl_grade_links.' WHERE id='.$get_delete_link.' AND type = '.LINK_FORUM_THREAD.');';
 			Database::query($sql);
 			// clean attendance
-			$sql = 'UPDATE '.$tbl_attendance.' SET attendance_qualify_max=0, attendance_weight = 0, attendance_qualify_title="" 
+			$sql = 'UPDATE '.$tbl_attendance.' SET attendance_qualify_max=0, attendance_weight = 0, attendance_qualify_title=""
 				 	WHERE c_id = '.$course_id.' AND id = (SELECT ref_id FROM '.$tbl_grade_links.' WHERE id='.$get_delete_link.' AND type = '.LINK_ATTENDANCE.');';
 			Database::query($sql);
 			$link[0]->delete();
@@ -441,7 +439,7 @@ switch ($action) {
             $category_to_lock[0]->lock_all_items(0);
             $confirmation_message = get_lang('EvaluationHasBeenUnLocked');
         }
-        break;    
+        break;
 }
 
 //actions on the sortabletable
@@ -454,7 +452,7 @@ if (isset ($_POST['action'])) {
 		$filter_warning_msg = false;
 	} else {
 		switch ($_POST['action']) {
- 
+
 			case 'deleted' :
 				$number_of_deleted_categories= 0;
 				$number_of_deleted_evaluations= 0;
@@ -620,8 +618,8 @@ if (empty ($_GET['selectcat'])) {
 }
 $simple_search_form='';
 
-if (isset($_GET['studentoverview'])) {    
-    //@todo this code also seems to be deprecated ...    
+if (isset($_GET['studentoverview'])) {
+    //@todo this code also seems to be deprecated ...
 	$cats= Category :: load($category);
 	$stud_id= (api_is_allowed_to_edit() ? null : $stud_id);
 	$allcat= array ();
@@ -635,7 +633,7 @@ if (isset($_GET['studentoverview'])) {
 		foreach ($data_array as $data) {
 			$newarray[] = array_slice($data, 1);
 		}
-		$pdf= new Cezpdf(); 
+		$pdf= new Cezpdf();
 		$pdf->selectFont(api_get_path(LIBRARY_PATH).'ezpdf/fonts/Courier.afm');
 		$pdf->ezSetMargins(30, 30, 50, 30);
 		$pdf->ezSetY(810);
@@ -649,15 +647,15 @@ if (isset($_GET['studentoverview'])) {
     }
 } else {
     //Student view
-    
+
     //in any other case (no search, no pdf), print the available gradebooks
     // Important note: loading a category will actually load the *contents* of
     // this category. This means that, to show the categories of a course,
     // we have to show the root category and show its subcategories that
     // are inside this course. This is done at the time of calling
     // $cats[0]->get_subcategories(), not at the time of doing Category::load()
-    // $category comes from GET['selectcat']    
-    
+    // $category comes from GET['selectcat']
+
     //if $category = 0 (which happens when GET['selectcat'] is undefined)
     // then Category::load() will create a new 'root' category with empty
     // course and session fields in memory (Category::create_root_category())
@@ -676,8 +674,8 @@ if (isset($_GET['studentoverview'])) {
 	    $cats = Category :: load(null, null, $course_code, null, null, $session_id, false);
         if (empty($cats)) {
             // There is no category for this course+session, so create one
-            $cat= new Category();     
-            if (!empty($session_id)) {            	
+            $cat= new Category();
+            if (!empty($session_id)) {
                 $s_name = api_get_session_name($session_id);
             	$cat->set_name($course_code.' - '.get_lang('Session').' '.$s_name);
                 $cat->set_session_id($session_id);
@@ -707,7 +705,7 @@ if (isset($_GET['studentoverview'])) {
     } else {
     	$stud_id = $stud_id;
     }
-    
+
 	$allcat  = $cats[0]->get_subcategories($stud_id, $course_code, $session_id);
 	$alleval = $cats[0]->get_evaluations($stud_id);
 	$alllink = $cats[0]->get_links($stud_id);
@@ -735,14 +733,14 @@ if ($category != '0') {
 	$category_id   = intval($_GET['selectcat']);
 	$course_id     = Database::get_course_by_category($category_id);
 	$show_message  = $cat->show_message_resource_delete($course_id);
-    
+
 	if ($show_message == '') {
 		//student
 		if (!api_is_allowed_to_edit()) {
             $certificate_html = Category::register_user_certificate($category_id, $stud_id);
             if ($certificate_html) {
                 echo $certificate_html;
-            }            
+            }
 		} //end hack
 	}
 }
@@ -751,45 +749,45 @@ if (api_is_allowed_to_edit(null, true)) {
 	// Tool introduction
 	Display::display_introduction_section(TOOL_GRADEBOOK, array('ToolbarSet' => 'AssessmentsIntroduction'));
 
-	if ( (isset ($_GET['selectcat']) && $_GET['selectcat']<>0) ) {	    
+	if ( (isset ($_GET['selectcat']) && $_GET['selectcat']<>0) ) {
 	//
-	} else {	    
+	} else {
         if (((isset ($_GET['selectcat']) && $_GET['selectcat']==0) || ((isset($_GET['cidReq']) && $_GET['cidReq']!==''))) || isset($_GET['isStudentView']) && $_GET['isStudentView']=='false') {
-            $cats = Category :: load(null, null, $course_code, null, null, $session_id, false);		
+            $cats = Category :: load(null, null, $course_code, null, null, $session_id, false);
 		}
 	}
 }
 
 if (isset($first_time) && $first_time==1 && api_is_allowed_to_edit(null,true)) {
 	echo '<meta http-equiv="refresh" content="0;url='.api_get_self().'?cidReq='.$course_code.'" />';
-} else {    
+} else {
     $cats = Category :: load(null, null, $course_code, null, null, $session_id, false); //already init
-    
+
 	if (!empty($cats)) {
-        
-        if ( (api_get_setting('gradebook_enable_grade_model') == 'true') && 
+
+        if ( (api_get_setting('gradebook_enable_grade_model') == 'true') &&
              (api_is_platform_admin() || (api_is_allowed_to_edit(null, true) && api_get_setting('teachers_can_change_grade_model_settings') == 'true'))) {
-            
+
             //Getting grade models
             $obj = new GradeModel();
             $grade_models = $obj->get_all();
             $grade_model_id = $cats[0]->get_grade_model_id();
-                                    
+
             //No children
             if ( (count($cats) == 1 && empty($grade_model_id)) || (count($cats) == 1 && $grade_model_id != -1) ) {
-                if (!empty($grade_models)) {                   
-                    $form_grade = new FormValidator('grade_model_settings');                    
+                if (!empty($grade_models)) {
+                    $form_grade = new FormValidator('grade_model_settings');
                     $obj->fill_grade_model_select_in_form($form_grade, 'grade_model_id', $grade_model_id);
                     $form_grade->addElement('style_submit_button', 'submit', get_lang('Save'), 'class="save"');
-                    
+
                     if ($form_grade->validate()) {
                         $value = $form_grade->exportValue('grade_model_id');
-                        
+
                         $gradebook = new Gradebook();
-                        $gradebook->update(array('id'=> $cats[0]->get_id(), 'grade_model_id' => $value), true);                 
+                        $gradebook->update(array('id'=> $cats[0]->get_id(), 'grade_model_id' => $value), true);
 
-                        //do something                        
-                        $obj = new GradeModel();                             
+                        //do something
+                        $obj = new GradeModel();
                         $components = $obj->get_components($value);
 
                         foreach ($components as $component) {
@@ -810,34 +808,34 @@ if (isset($first_time) && $first_time==1 && api_is_allowed_to_edit(null,true)) {
                         //Reloading cats
                         $cats = Category :: load(null, null, $course_code, null, null, $session_id, false);
                     } else {
-                        $form_grade->display();   
+                        $form_grade->display();
                     }
                 }
             }
         }
-        
+
 		$i = 0;
-        
-		foreach ($cats as $cat) {			
-			$allcat  = $cat->get_subcategories($stud_id, $course_code, $session_id);            
+
+		foreach ($cats as $cat) {
+			$allcat  = $cat->get_subcategories($stud_id, $course_code, $session_id);
 			$alleval = $cat->get_evaluations($stud_id);
 			$alllink = $cat->get_links($stud_id);
-			
+
 			if ($cat->get_parent_id() != 0 ) {
 				$i++;
 			} else {
-				//This is the father				
+				//This is the father
 				//Create gradebook/add gradebook links
-                DisplayGradebook::display_header_gradebook($cat, 0, $cat->get_id(), $is_course_admin, $is_platform_admin, $simple_search_form, false, true);				
-				
+                DisplayGradebook::display_header_gradebook($cat, 0, $cat->get_id(), $is_course_admin, $is_platform_admin, $simple_search_form, false, true);
+
 				if (api_is_allowed_to_edit(null,true) && api_get_setting('gradebook_enable_grade_model') == 'true') {
 					//Showing the grading system
-					if (!empty($grade_models[$grade_model_id])) {             
+					if (!empty($grade_models[$grade_model_id])) {
                         Display::display_normal_message(get_lang('GradeModel').': '.$grade_models[$grade_model_id]['name']);
-                    }					
-				}                                
-				$gradebooktable = new GradebookTable($cat, $allcat, $alleval, $alllink, $addparams);                
-				$gradebooktable->display();				
+                    }
+				}
+				$gradebooktable = new GradebookTable($cat, $allcat, $alleval, $alllink, $addparams);
+				$gradebooktable->display();
 			}
 		}
 	}
diff --git a/main/gradebook/lib/be/category.class.php b/main/gradebook/lib/be/category.class.php
index 829e0a4ed6..65a8cb890b 100644
--- a/main/gradebook/lib/be/category.class.php
+++ b/main/gradebook/lib/be/category.class.php
@@ -7,9 +7,6 @@
 /**
  * Init
  */
-require_once api_get_path(LIBRARY_PATH).'skill.lib.php';
-require_once api_get_path(LIBRARY_PATH).'gradebook.lib.php';
-require_once api_get_path(LIBRARY_PATH).'grade_model.lib.php';
 /**
  * Class
  * @package chamilo.gradebook
diff --git a/main/gradebook/lib/fe/exportgradebook.php b/main/gradebook/lib/fe/exportgradebook.php
index 8231ce05cc..293c17bd41 100644
--- a/main/gradebook/lib/fe/exportgradebook.php
+++ b/main/gradebook/lib/fe/exportgradebook.php
@@ -94,7 +94,6 @@ a:active {text-decoration: none; font-weight : bold;  color : black;}
  * @return void
  */
 function export_pdf_attendance($headers_table, $data_table, $headers_pdf, $footers_pdf, $title_pdf) {
-    require_once api_get_path(LIBRARY_PATH).'mpdf/mpdf.php';
 
     $mpdf = new mPDF('UTF-8', 'A4-L', '', '', 15, 10, 35, 20, 4, 2, 'L');
     $mpdf->useOnlyCoreFonts = true;
@@ -219,46 +218,45 @@ function export_pdf_attendance($headers_table, $data_table, $headers_pdf, $foote
  * @param	array	pdf footers
  * @return void
  */
-function export_pdf_with_html($headers_table, $data_table, $headers_pdf, $footers_pdf, $title_pdf) {
-	
-	require_once api_get_path(LIBRARY_PATH).'pdf.lib.php';
+function export_pdf_with_html($headers_table, $data_table, $headers_pdf, $footers_pdf, $title_pdf)
+{
 	$headers_in_pdf = '<img src="'.api_get_path(WEB_CSS_PATH).api_get_setting('stylesheets').'/images/header-logo.png">';
-    
+
 	if (is_array($headers_pdf)) {
 		// preparing headers pdf
-		$header = '<br/><br/><table width="100%" cellspacing="1" cellpadding="5" border="0" class="strong">							
-					        <tr><td width="100%" style="text-align: center;" class="title" colspan="4"><h1>'.$title_pdf.'</h1></td></tr>';		
-		foreach($headers_pdf as $header_pdf) {			
+		$header = '<br/><br/><table width="100%" cellspacing="1" cellpadding="5" border="0" class="strong">
+					        <tr><td width="100%" style="text-align: center;" class="title" colspan="4"><h1>'.$title_pdf.'</h1></td></tr>';
+		foreach($headers_pdf as $header_pdf) {
 			if (!empty($header_pdf[0]) && !empty($header_pdf[1])) {
 				$header.= '<tr><td><strong>'.$header_pdf[0].'</strong> </td><td>'.$header_pdf[1].'</td></tr>';
 			}
-		}		
+		}
 		$header.='</table><br />';
 	}
-		
+
 	// preparing footer pdf
 	$footer = '<table width="100%" cellspacing="2" cellpadding="10" border="0">';
 	if (is_array($footers_pdf)) {
-		$footer .= '<tr>';	
+		$footer .= '<tr>';
 		foreach ($footers_pdf as $foot_pdf) {
 			$footer .= '<td width="33%" style="text-align: center;">'.$foot_pdf.'</td>';
 		}
-		$footer .= '</tr>';	
+		$footer .= '</tr>';
 	}
-	$footer .= '</table>';	
+	$footer .= '</table>';
 	$footer .= '<div align="right" style="font-weight: bold;">{PAGENO}/{nb}</div>';
-	
-	// preparing content pdf		
+
+	// preparing content pdf
 	$css_file = api_get_path(TO_SYS, WEB_CSS_PATH).api_get_setting('stylesheets').'/print.css';
 	if (file_exists($css_file)) {
 		$css = @file_get_contents($css_file);
 	} else {
 		$css = '';
-	}	
+	}
 	$items_per_page = 30;
-	$count_pages = ceil(count($data_table) / $items_per_page);  
+	$count_pages = ceil(count($data_table) / $items_per_page);
 	for ($x = 0; $x<$count_pages; $x++) {
-		$content_table .= '<table width="100%" border="1" style="border-collapse:collapse">';	
+		$content_table .= '<table width="100%" border="1" style="border-collapse:collapse">';
 		// header table
 		$content_table .= '<tr>';
 		$i = 0;
@@ -267,38 +265,38 @@ function export_pdf_with_html($headers_table, $data_table, $headers_pdf, $footer
 				if (!empty($head_table[0])) {
 					$width = (!empty($head_table[1])?$head_table[1].'%':'');
 					$content_table .= '<th width="'.$width.'">'.$head_table[0].'</th>';
-					$i++;	
-				}			
-			}		
-		}	
-		$content_table .= '</tr>';			
+					$i++;
+				}
+			}
+		}
+		$content_table .= '</tr>';
 		// body table
-		
+
 		if (is_array($data_table) && count($data_table) > 0) {
-			$offset = $x*$items_per_page;				
+			$offset = $x*$items_per_page;
 			$data_table = array_slice ($data_table, $offset, count($data_table));
 			$i = 1;
 			$item = $offset+1;
-			foreach ($data_table as $data) {			
+			foreach ($data_table as $data) {
 				$content_table .= '<tr>';
 				$content_table .= '<td>'.($item<10?'0'.$item:$item).'</td>';
-				foreach ($data as  $key => $content) {							
+				foreach ($data as  $key => $content) {
 					if (isset($content)) {
 						$key == 1 ? $align='align="left"':$align='align="center"';
-						$content_table .= '<td '.$align.' style="padding:4px;" >'.$content.'</td>';	
-					}					
+						$content_table .= '<td '.$align.' style="padding:4px;" >'.$content.'</td>';
+					}
 				}
 				$content_table .= '</tr>';
 				$i++;
 				$item++;
 				if ($i > $items_per_page) { break; }
-			}			
+			}
 		} else {
 			$content_table .= '<tr colspan="'.$i.'"><td>'.get_lang('Empty').'</td></tr>';
-		}	
-		$content_table .= '</table>';				
-		if ($x < ($count_pages - 1)) { $content_table .= '<pagebreak />'; }		
-	}	
+		}
+		$content_table .= '</table>';
+		if ($x < ($count_pages - 1)) { $content_table .= '<pagebreak />'; }
+	}
 	$pdf = new PDF();
     $pdf->set_custom_footer($footer);
     $pdf->set_custom_header($headers_in_pdf);
diff --git a/main/gradebook/lib/fe/flatviewtable.class.php b/main/gradebook/lib/fe/flatviewtable.class.php
index 9c20a5416f..aa269802cd 100644
--- a/main/gradebook/lib/fe/flatviewtable.class.php
+++ b/main/gradebook/lib/fe/flatviewtable.class.php
@@ -32,13 +32,13 @@ class FlatViewTable extends SortableTable
 		parent :: __construct ('flatviewlist', null, null, (api_is_western_name_order() xor api_sort_by_first_name()) ? 1 : 0);
         $this->selectcat = $selectcat;
         $this->datagen = new FlatViewDataGenerator($users, $evals, $links, array('only_subcat'=>$this->selectcat->get_id()));
-        		
+
 		$this->limit_enabled = $limit_enabled;
 		$this->offset = $offset;
 		if (isset ($addparams)) {
 			$this->set_additional_parameters($addparams);
 		}
-		
+
 		// step 2: generate rows: students
 		$this->datagen->category = $this->selectcat;
 	}
@@ -53,20 +53,20 @@ class FlatViewTable extends SortableTable
 
 		$header_name = $this->datagen->get_header_names();
 		$total_users = $this->datagen->get_total_users_count();
-		
+
 		$img_file = '';
-		
+
 		if ($this->datagen->get_total_items_count()>0 && $total_users > 0 ) {
 		    //Removing user names and total
 			array_shift($header_name);
 			array_shift($header_name);
 			array_pop($header_name);
-			
+
 			$user_results = $this->datagen->get_data_to_graph();
-						
+
 			$pre_result = $new_result = array();
 			$DataSet = new pData();
-			
+
 			//$pre_result total score of students
 			//filling the Dataset
 			foreach($user_results as $result) {
@@ -76,15 +76,15 @@ class FlatViewTable extends SortableTable
 			}
 			$i = 1;
 			$show_draw = false;
-			if ($total_users >0 ) {			    
+			if ($total_users >0 ) {
 				foreach($pre_result as $res) {
-					$total =  $res / ($total_users);										
+					$total =  $res / ($total_users);
 					if ($total != 0) {
 						$show_draw  = true;
 					}
 					$DataSet->AddPoint($total, "Serie".$i);
 					$DataSet->SetSerieName(strip_tags($header_name[$i-1]),"Serie".$i);
-					
+
 					// Dataset definition
 					$DataSet->AddAllSeries();
 					$DataSet->SetAbsciseLabelSerie();
@@ -98,7 +98,7 @@ class FlatViewTable extends SortableTable
 			$gradebook_id = intval($_GET['selectcat']);
 			$graph_id = api_get_user_id().'AverageResultsVsResource'.$gradebook_id.api_get_course_id();
 			$data = $DataSet->GetData();
-			
+
 			if ($show_draw) {
 				if ($Cache->IsInCache($graph_id, $DataSet->GetData())) {
 				//if (0) {
@@ -130,7 +130,7 @@ class FlatViewTable extends SortableTable
 					//background color area & stripe or not
 					$Test->drawGraphArea(255,255,255,TRUE);
 					$Test->drawScale($DataSet->GetData(), $DataSet->GetDataDescription(), SCALE_START0 ,150,150,150,TRUE,0,1, FALSE);
-					
+
 					//background grid
 					$Test->drawGrid(4,TRUE,230,230,230,50);
 
@@ -163,9 +163,6 @@ class FlatViewTable extends SortableTable
 	}
 
 	function display_graph_by_resource() {
-		require_once api_get_path(LIBRARY_PATH).'pchart/pData.class.php';
-		require_once api_get_path(LIBRARY_PATH).'pchart/pChart.class.php';
-		require_once api_get_path(LIBRARY_PATH).'pchart/pCache.class.php';
 
 		$header_name = $this->datagen->get_header_names();
 		$total_users = $this->datagen->get_total_users_count();
@@ -176,13 +173,13 @@ class FlatViewTable extends SortableTable
 			array_shift($header_name);
 			//Removing last name
 			array_shift($header_name);
-            
+
 			$displayscore = ScoreDisplay :: instance();
-			$customdisplays = $displayscore->get_custom_score_display_settings();		
-			
+			$customdisplays = $displayscore->get_custom_score_display_settings();
+
 			if (is_array($customdisplays) && count(($customdisplays))) {
-			    
-				$user_results = $this->datagen->get_data_to_graph2();				
+
+				$user_results = $this->datagen->get_data_to_graph2();
 				$pre_result = $new_result = array();
 				$DataSet = new pData();
 				//filling the Dataset
@@ -192,7 +189,7 @@ class FlatViewTable extends SortableTable
 						$pre_result[$i+3][]= $result[$i+1];
 					}
 				}
-	
+
 				$i=0;
 				$show_draw = false;
 				$resource_list = array();
@@ -202,11 +199,11 @@ class FlatViewTable extends SortableTable
 					rsort($res_array);
 					$pre_result2[] = $res_array;
 				}
-				
+
 				//@todo when a display custom does not exist the order of the color does not match
 				//filling all the answer that are not responded with 0
 				rsort($customdisplays);
-				
+
 				if ($total_users > 0) {
 					foreach($pre_result2 as $key=>$res_array) {
 						$key_list = array();
@@ -214,22 +211,22 @@ class FlatViewTable extends SortableTable
 							$resource_list[$key][$user_result[1]] += 1;
 							$key_list[] = $user_result[1];
 						}
-				
+
 						foreach ($customdisplays as $display) {
 							if (!in_array($display['display'], $key_list))
 								$resource_list[$key][$display['display']] = 0;
 						}
 						$i++;
 					}
-				}				
-				
-				//fixing $resource_list		
-				$max = 0;		
+				}
+
+				//fixing $resource_list
+				$max = 0;
 				$new_list = array();
 				foreach($resource_list as $key=>$value) {
 				    $new_value = array();
-				    
-				    foreach($customdisplays as $item) {				        
+
+				    foreach($customdisplays as $item) {
 				        if ($value[$item['display']] > $max) {
 				            $max = $value[$item['display']];
 				        }
@@ -237,8 +234,8 @@ class FlatViewTable extends SortableTable
 				    }
 				    $new_list[] = $new_value;
 				}
-				$resource_list = $new_list;				
-				
+				$resource_list = $new_list;
+
 				$i = 1;
 				$j = 0;
 
@@ -290,12 +287,12 @@ class FlatViewTable extends SortableTable
 
 							//background color area & stripe or not
 							$Test->drawGraphArea(255,255,255,TRUE);
-							
+
 							//Setting max height by default see #3296
 						    if (!empty($max)) {
-                                $Test->setFixedScale(0, $max);    
+                                $Test->setFixedScale(0, $max);
 						    }
-							
+
 							$Test->drawScale($DataSet->GetData(),$DataSet->GetDataDescription(), SCALE_ADDALLSTART0, 150,150,150, TRUE, 0, 0, FALSE);
 
 							//background grid
@@ -433,7 +430,7 @@ class FlatViewTable extends SortableTable
 	      							.'?selectcat='.Security::remove_XSS($_GET['selectcat'])
 	      							.'&offset='.(($this->offset)-LIMIT)
 									.(isset($_GET['search'])?'&search='.Security::remove_XSS($_GET['search']):'').'">'
-	      					.Display::return_icon('action_prev.png', get_lang('PreviousPage'), array(), 32)	      					
+	      					.Display::return_icon('action_prev.png', get_lang('PreviousPage'), array(), 32)
 	      					.'</a>';
 	      	} else {
 	      		$header .= Display::return_icon('action_prev_na.png', get_lang('PreviousPage'), array(), 32);
@@ -442,7 +439,7 @@ class FlatViewTable extends SortableTable
 			// next X
 	      	$calcnext = (($this->offset+(2*LIMIT)) > $totalitems) ?
 	      					($totalitems-(LIMIT+$this->offset)) : LIMIT;
-      		
+
       		if ($calcnext > 0) {
 	      		$header .= '<a href="'.api_get_self()
 	      							.'?selectcat='.Security::remove_XSS($_GET['selectcat'])
@@ -474,14 +471,14 @@ class FlatViewTable extends SortableTable
 		$header_names = $this->datagen->get_header_names($this->offset, $selectlimit);
 
 		$column = 0;
-        
+
 		if ($is_western_name_order) {
 			$this->set_header($column++, $header_names[1]);
 			$this->set_header($column++, $header_names[0]);
 		} else {
 			$this->set_header($column++, $header_names[0]);
 			$this->set_header($column++, $header_names[1]);
-		}        
+		}
 
 		while ($column < count($header_names)) {
 			$this->set_header($column, $header_names[$column], false);
diff --git a/main/gradebook/lib/fe/userform.class.php b/main/gradebook/lib/fe/userform.class.php
index d0bc60f0b4..5cb469b726 100644
--- a/main/gradebook/lib/fe/userform.class.php
+++ b/main/gradebook/lib/fe/userform.class.php
@@ -10,7 +10,6 @@
 require_once dirname(__FILE__).'/../../../inc/global.inc.php';
 require_once dirname(__FILE__).'/../be.inc.php';
 require_once dirname(__FILE__).'/../gradebook_functions.inc.php';
-require_once api_get_path(LIBRARY_PATH) . 'formvalidator/FormValidator.class.php';
 /**
  * Extends formvalidator with import and export forms
  * @author Stijn Konings
diff --git a/main/gradebook/user_stats.php b/main/gradebook/user_stats.php
index 7ba3d50753..9164b252b2 100644
--- a/main/gradebook/user_stats.php
+++ b/main/gradebook/user_stats.php
@@ -84,7 +84,6 @@ if (isset ($_GET['exportpdf'])) {
     }
     $html .= $table->toHtml();
 
-    require_once api_get_path(LIBRARY_PATH).'pdf.lib.php';
     $pdf = new PDF();
     $pdf->content_to_pdf($html);
 	exit;
diff --git a/main/help/allowed_html_tags.php b/main/help/allowed_html_tags.php
index 4cd419448d..8096c3cd3b 100755
--- a/main/help/allowed_html_tags.php
+++ b/main/help/allowed_html_tags.php
@@ -14,8 +14,7 @@
 // Language file that needs to be included
 $language_file = 'help';
 
-require '../inc/global.inc.php';
-require_once api_get_path(LIBRARY_PATH).'formvalidator/FormValidator.class.php';
+require_once '../inc/global.inc.php';
 require_once api_get_path(LIBRARY_PATH).'formvalidator/Rule/HTML.php';
 
 header('Content-Type: text/html; charset='.api_get_system_encoding());
diff --git a/main/inc/ajax/course.ajax.php b/main/inc/ajax/course.ajax.php
index d7a473c579..66a83f46da 100644
--- a/main/inc/ajax/course.ajax.php
+++ b/main/inc/ajax/course.ajax.php
@@ -11,36 +11,36 @@ $action = $_REQUEST['a'];
 
 $user_id = api_get_user_id();
 
-switch ($action) {    
+switch ($action) {
     case 'add_course_vote':
-		
+
 		$course_id = intval($_REQUEST['course_id']);
         $star      = intval($_REQUEST['star']);
-		
-        if (!api_is_anonymous()) {     	    
-            CourseManager::add_course_vote($user_id, $star, $course_id, 0);                
-        }		
-		$point_info = CourseManager::get_course_ranking($course_id, 0); 		
-		$ajax_url = api_get_path(WEB_AJAX_PATH).'course.ajax.php?a=add_course_vote';		
+
+        if (!api_is_anonymous()) {
+            CourseManager::add_course_vote($user_id, $star, $course_id, 0);
+        }
+		$point_info = CourseManager::get_course_ranking($course_id, 0);
+		$ajax_url = api_get_path(WEB_AJAX_PATH).'course.ajax.php?a=add_course_vote';
 	    $rating = Display::return_rating_system('star_'.$course_id, $ajax_url.'&amp;course_id='.$course_id, $point_info, false);
 		echo $rating;
-		
+
         break;
     case  'get_user_courses':
         if (api_is_platform_admin()) {
-            $user_id = intval($_POST['user_id']);            
+            $user_id = intval($_POST['user_id']);
             $list_course_all_info = CourseManager::get_courses_list_by_user_id($user_id, false);
             if (!empty($list_course_all_info)) {
-                foreach($list_course_all_info as $course_item) {                
-                    $course_info = api_get_course_info($course_item['code']);                    
+                foreach($list_course_all_info as $course_item) {
+                    $course_info = api_get_course_info($course_item['code']);
                     echo $course_info['title'].'<br />';
                 }
-            } else {            
+            } else {
                 echo get_lang('UserHasNoCourse');
-            } 
+            }
         }
         break;
     default:
         echo '';
 }
-exit;
+exit;
\ No newline at end of file
diff --git a/main/inc/ajax/course_home.ajax.php b/main/inc/ajax/course_home.ajax.php
index 30ef3f119b..5b926204db 100644
--- a/main/inc/ajax/course_home.ajax.php
+++ b/main/inc/ajax/course_home.ajax.php
@@ -468,4 +468,4 @@ switch ($action) {
 	default:
 		echo '';
 }
-exit;
+exit;
\ No newline at end of file
diff --git a/main/inc/ajax/exercise.ajax.php b/main/inc/ajax/exercise.ajax.php
index 1981e81ec8..244402368a 100644
--- a/main/inc/ajax/exercise.ajax.php
+++ b/main/inc/ajax/exercise.ajax.php
@@ -408,4 +408,4 @@ switch ($action) {
     default:
         echo '';
 }
-exit;
+exit;
\ No newline at end of file
diff --git a/main/inc/ajax/extra_field.ajax.php b/main/inc/ajax/extra_field.ajax.php
index 42ff016b49..84ba646578 100644
--- a/main/inc/ajax/extra_field.ajax.php
+++ b/main/inc/ajax/extra_field.ajax.php
@@ -1,21 +1,23 @@
 <?php
+/* For licensing terms, see /license.txt */
 
 $language_file = array('admin', 'registration', 'userInfo');
 require_once '../global.inc.php';
 $action = $_GET['a'];
 
-switch ($action) {	
+switch ($action) {
     case 'get_second_select_options':
         $type = isset($_REQUEST['type']) ? $_REQUEST['type'] : null;
         $field_id = isset($_REQUEST['field_id']) ? $_REQUEST['field_id'] : null;
         $option_value_id = isset($_REQUEST['option_value_id']) ? $_REQUEST['option_value_id'] : null;
-        
+
         if (!empty($type) && !empty($field_id) && !empty($option_value_id)) {
             $field_options = new ExtraFieldOption($type);
-            echo $field_options->get_second_select_field_options_by_field($field_id, $option_value_id, true);           
+            echo $field_options->get_second_select_field_options_by_field($field_id, $option_value_id, true);
         }
         break;
     default:
         exit;
         break;
-}
\ No newline at end of file
+}
+exit;
\ No newline at end of file
diff --git a/main/inc/ajax/install.ajax.php b/main/inc/ajax/install.ajax.php
index 20e6d7e57b..c30f129203 100644
--- a/main/inc/ajax/install.ajax.php
+++ b/main/inc/ajax/install.ajax.php
@@ -10,59 +10,58 @@ $action = $_GET['a'];
 
 switch ($action) {
 	case 'send_contact_information':
-			if (!empty($_POST)) {          
-                            // get params from contact form
-                            $person_name = $_POST['person_name'];
-                            $person_email = $_POST['person_email'];
-                            $person_role = $_POST['person_role'];
-                            $financial_decision = $_POST['financial_decision'];
-                            $contact_language = $_POST['language'];
-                            $company_name = $_POST['company_name'];
-                            $company_activity = $_POST['company_activity'];
-                            $company_country = $_POST['company_country'];
-                            $company_city = $_POST['company_city']; 
+        if (!empty($_POST)) {
+            // get params from contact form
+            $person_name = $_POST['person_name'];
+            $person_email = $_POST['person_email'];
+            $person_role = $_POST['person_role'];
+            $financial_decision = $_POST['financial_decision'];
+            $contact_language = $_POST['language'];
+            $company_name = $_POST['company_name'];
+            $company_activity = $_POST['company_activity'];
+            $company_country = $_POST['company_country'];
+            $company_city = $_POST['company_city'];
 
-                            // validating required fields
-                            $a_required_fields = array($person_name, $person_role, $company_name, $company_activity, $company_country);
-                            $required_field_error = false;
-                            foreach($a_required_fields as $required_file) {
-                                if (trim($required_file) === '') {
-                                    $required_field_error = true;
-                                    break;
-                                }
-                            }
+            // validating required fields
+            $a_required_fields = array($person_name, $person_role, $company_name, $company_activity, $company_country);
+            $required_field_error = false;
+            foreach($a_required_fields as $required_file) {
+                if (trim($required_file) === '') {
+                    $required_field_error = true;
+                    break;
+                }
+            }
 
-                            if ($required_field_error) {
-                                echo 'required_field_error';
-                            } else {
+            if ($required_field_error) {
+                echo 'required_field_error';
+            } else {
 
-                                // save contact information with web service                                
-                                require_once '../lib/nusoap/nusoap.php';
+                // save contact information with web service
+                require_once '../lib/nusoap/nusoap.php';
 
-                                // create a client
-                                $client = new nusoap_client('http://version.chamilo.org/contact.php?wsdl', true);
+                // create a client
+                $client = new nusoap_client('http://version.chamilo.org/contact.php?wsdl', true);
 
-                                // call method ws_add_contact_information
-                                $contact_params = array(
-                                                        'person_name' => $person_name,
-                                                        'person_email' => $person_email,
-                                                        'person_role' => $person_role,
-                                                        'financial_decision' => $financial_decision,
-                                                        'contact_language' => $contact_language,
-                                                        'company_name' => $company_name,
-                                                        'company_activity' => $company_activity,
-                                                        'company_country' => $company_country,
-                                                        'company_city' => $company_city
-                                                    );
+                // call method ws_add_contact_information
+                $contact_params = array(
+                    'person_name' => $person_name,
+                    'person_email' => $person_email,
+                    'person_role' => $person_role,
+                    'financial_decision' => $financial_decision,
+                    'contact_language' => $contact_language,
+                    'company_name' => $company_name,
+                    'company_activity' => $company_activity,
+                    'company_country' => $company_country,
+                    'company_city' => $company_city
+                );
 
-                                $result = $client->call('ws_add_contact_information', array('contact_params' => $contact_params));
-								
-								echo $result;
-							}
+                $result = $client->call('ws_add_contact_information', array('contact_params' => $contact_params));
 
-				}
-			break;	
-	default:
-		echo '';
+                echo $result;
+            }
+        }
+    break;
+default:
+    echo '';
 }
 exit;
\ No newline at end of file
diff --git a/main/inc/ajax/link.ajax.php b/main/inc/ajax/link.ajax.php
index cf424d6457..e7a5ffcddd 100644
--- a/main/inc/ajax/link.ajax.php
+++ b/main/inc/ajax/link.ajax.php
@@ -10,36 +10,36 @@ api_protect_course_script(true);
 
 $action = $_REQUEST['a'];
 
-switch ($action) {    
+switch ($action) {
     case 'check_url':
         if (api_is_allowed_to_edit(null, true)) {
             $url = $_REQUEST['url'];
-                        
-            //Check if curl is available            
+
+            //Check if curl is available
             if  (!in_array('curl', get_loaded_extensions())) {
                 echo '';
                 exit;
             }
-            
-            // set URL and other appropriate options            
+
+            // set URL and other appropriate options
             $defaults = array(
                 CURLOPT_URL => $url,
-                CURLOPT_FOLLOWLOCATION => true,         // follow redirects accept youtube.com                
+                CURLOPT_FOLLOWLOCATION => true,         // follow redirects accept youtube.com
                 CURLOPT_HEADER => 0,
                 CURLOPT_RETURNTRANSFER => true,
                 CURLOPT_TIMEOUT => 4
             );
             //create a new cURL resource
-            
+
             $ch = curl_init();
-            curl_setopt_array($ch, $defaults);        
-            
+            curl_setopt_array($ch, $defaults);
+
             // grab URL and pass it to the browser
-            $result = curl_exec($ch);    
-            
+            $result = curl_exec($ch);
+
             // close cURL resource, and free up system resources
             curl_close($ch);
-            
+
             if ($result) {
                 echo Display::return_icon('accept.png', get_lang('Ok'));
             } else {
@@ -50,4 +50,4 @@ switch ($action) {
     default:
         echo '';
 }
-exit;
+exit;
\ No newline at end of file
diff --git a/main/inc/ajax/notebook.ajax.php b/main/inc/ajax/notebook.ajax.php
index 93342c2945..55ba38f1d4 100644
--- a/main/inc/ajax/notebook.ajax.php
+++ b/main/inc/ajax/notebook.ajax.php
@@ -1,7 +1,9 @@
 <?php
+/* For licensing terms, see /license.txt */
 
 namespace Notebook;
 
 require_once '../global.inc.php';
 
-AjaxController::instance()->run();
\ No newline at end of file
+AjaxController::instance()->run();
+exit;
\ No newline at end of file
diff --git a/main/inc/ajax/online.ajax.php b/main/inc/ajax/online.ajax.php
index 88acc5ddd3..0d4892c9f8 100644
--- a/main/inc/ajax/online.ajax.php
+++ b/main/inc/ajax/online.ajax.php
@@ -1,4 +1,5 @@
 <?php
+/* For licensing terms, see /license.txt */
 
 /*
  * To change this template, choose Tools | Templates
@@ -36,4 +37,5 @@ switch($action) {
         break;
     default:
         break;
-}
\ No newline at end of file
+}
+exit;
\ No newline at end of file
diff --git a/main/inc/ajax/skill.ajax.php b/main/inc/ajax/skill.ajax.php
index 264a579148..3f545a76b8 100644
--- a/main/inc/ajax/skill.ajax.php
+++ b/main/inc/ajax/skill.ajax.php
@@ -6,9 +6,6 @@
 
 require_once '../global.inc.php';
 
-require_once api_get_path(LIBRARY_PATH).'skill.lib.php';
-require_once api_get_path(LIBRARY_PATH).'gradebook.lib.php';
-
 $action = isset($_REQUEST['a']) ? $_REQUEST['a'] : null;
 
 if (api_get_setting('allow_skills_tool') != 'true') {
@@ -24,10 +21,10 @@ $skill_gradebook = new SkillRelGradebook();
 switch ($action) {
     case 'add':
         if (api_is_platform_admin() || api_is_drh()) {
-            if (isset($_REQUEST['id']) && !empty($_REQUEST['id'])) {            
-                $skill_id = $skill->edit($_REQUEST);    
+            if (isset($_REQUEST['id']) && !empty($_REQUEST['id'])) {
+                $skill_id = $skill->edit($_REQUEST);
             } else {
-                $skill_id = $skill->add($_REQUEST);    
+                $skill_id = $skill->add($_REQUEST);
             }
         }
         echo $skill_id;
@@ -35,19 +32,19 @@ switch ($action) {
         if (api_is_platform_admin() || api_is_drh()) {
             echo $skill->delete($_REQUEST['skill_id']);
         }
-        break;      
-    case 'find_skills':        
+        break;
+    case 'find_skills':
         $skills = $skill->find('all', array('where' => array('name LIKE %?% '=>$_REQUEST['tag'])));
-        $return_skills = array();    
+        $return_skills = array();
         foreach ($skills as $skill) {
             $skill['caption'] = $skill['name'];
             $skill['value'] =  $skill['id'];
             $return_skills[] = $skill;
-        }            
+        }
         echo json_encode($return_skills);
-        break;    
-    case 'get_gradebooks':        
-        $gradebooks = $gradebook_list = $gradebook->get_all();        
+        break;
+    case 'get_gradebooks':
+        $gradebooks = $gradebook_list = $gradebook->get_all();
         $gradebook_list = array();
         //Only course gradebook with certificate
         if (!empty($gradebooks)) {
@@ -59,31 +56,31 @@ switch ($action) {
                 } else {
                   //  $gradebook['name'] = $gradebook_list[$gradebook['parent_id']]['name'].' > '.$gradebook['name'];
                     //$gradebook_list[]  = $gradebook;
-                }               
+                }
             }
         }
         echo json_encode($gradebook_list);
         break;
-    case 'find_gradebooks':        
-        $gradebooks = $gradebook->find('all', array('where' => array('name LIKE %?% ' => $_REQUEST['tag'])));        
-        $return = array();    
+    case 'find_gradebooks':
+        $gradebooks = $gradebook->find('all', array('where' => array('name LIKE %?% ' => $_REQUEST['tag'])));
+        $return = array();
         foreach ($gradebooks as $item) {
             $item['caption'] = $item['name'];
             $item['value'] =  $item['id'];
             $return[] = $item;
-        }        
-        echo json_encode($return);        
+        }
+        echo json_encode($return);
         break;
-    case 'get_course_info_popup':        
+    case 'get_course_info_popup':
         $course_info = api_get_course_info($_REQUEST['code']);
         $course_info['course_code'] = $course_info['code'];
         $courses = CourseManager::process_hot_course_item(array($course_info));
-        Display::display_no_header();        
+        Display::display_no_header();
         Display::$global_template->assign('hot_courses', $courses);
         echo Display::$global_template->fetch('default/layout/hot_course_item_popup.tpl');
         break;
     case 'gradebook_exists':
-        $data = $gradebook->get($_REQUEST['gradebook_id']);        
+        $data = $gradebook->get($_REQUEST['gradebook_id']);
         if (!empty($data)) {
             echo 1;
         } else {
@@ -91,22 +88,22 @@ switch ($action) {
         }
         break;
     case 'get_skills_by_profile':
-        $skill_rel_profile   = new SkillRelProfile();       
+        $skill_rel_profile   = new SkillRelProfile();
         $profile_id = isset($_REQUEST['profile_id']) ? $_REQUEST['profile_id'] : null;
         $skills = $skill_rel_profile->get_skills_by_profile($profile_id);
         echo json_encode($skills);
         break;
     case 'get_saved_profiles':
         $skill_profile   = new SkillProfile();
-        $profiles = $skill_profile->get_all();        
-        Display::display_no_header();        
+        $profiles = $skill_profile->get_all();
+        Display::display_no_header();
         Display::$global_template->assign('profiles', $profiles);
         echo Display::$global_template->fetch('default/skill/profile_item.tpl');
-        break;    
+        break;
     case 'get_skills':
-        $load_user_data = isset($_REQUEST['load_user_data']) ? $_REQUEST['load_user_data'] : null;        
+        $load_user_data = isset($_REQUEST['load_user_data']) ? $_REQUEST['load_user_data'] : null;
         $id = intval($_REQUEST['id']);
-        $skills = $skill->get_all($load_user_data, false, $id);                    
+        $skills = $skill->get_all($load_user_data, false, $id);
         echo json_encode($skills);
         break;
     case 'get_skill_info':
@@ -116,8 +113,8 @@ switch ($action) {
         break;
     case 'get_skill_course_info':
         $id = isset($_REQUEST['id']) ? $_REQUEST['id'] : null;
-        $skill_info = $skill->get_skill_info($id);        
-        $courses = $skill->get_courses_by_skill($id);        
+        $skill_info = $skill->get_skill_info($id);
+        $courses = $skill->get_courses_by_skill($id);
         $html = '';
         if (!empty($courses)) {
             $html = sprintf(get_lang('ToGetToLearnXYouWillNeedToTakeOneOfTheFollowingCourses'), '<i>'.$skill_info['name'].'</i>').'<br />';
@@ -127,37 +124,37 @@ switch ($action) {
                 $html .= Display::url(sprintf(get_lang('SkillXWithCourseX'), $skill_info['name'], $course['title']), $url, $attributes).'<br />';
             }
         }
-        echo $html;    
+        echo $html;
         break;
-    case 'get_skills_tree_json':        
+    case 'get_skills_tree_json':
         $user_id    = isset($_REQUEST['load_user']) && $_REQUEST['load_user'] == 1 ? api_get_user_id() : 0;
         $skill_id   = isset($_REQUEST['skill_id']) ? $_REQUEST['skill_id'] : 0;
-        $depth      = isset($_REQUEST['main_depth']) ? $_REQUEST['main_depth'] : 2;        
+        $depth      = isset($_REQUEST['main_depth']) ? $_REQUEST['main_depth'] : 2;
         $all = $skill->get_skills_tree_json($user_id, $skill_id, false, $depth);
         echo $all;
         break;
     case 'get_user_skills':
-        $skills = $skill->get_user_skills($user_id, true);        
-        Display::display_no_header();        
+        $skills = $skill->get_user_skills($user_id, true);
+        Display::display_no_header();
         Display::$global_template->assign('skills', $skills);
         echo Display::$global_template->fetch('default/skill/user_skills.tpl');
         break;
     case 'get_gradebook_info':
         $id = isset($_REQUEST['id']) ? $_REQUEST['id'] : null;
-        $info = $gradebook->get($id);                    
+        $info = $gradebook->get($id);
         echo json_encode($info);
-        break;  
+        break;
     case 'load_children':
         $id             = isset($_REQUEST['id']) ? $_REQUEST['id'] : null;
         $load_user_data = isset($_REQUEST['load_user_data']) ? $_REQUEST['load_user_data'] : null;
         $skills = $skill->get_children($id, $load_user_data);
-        
+
         $return = array();
         foreach ($skills as $skill) {
             if (isset($skill['data']) && !empty($skill['data'])) {
                 $return[$skill['data']['id']] = array(
                                                     'id'    => $skill['data']['id'],
-                                                    'name'  => $skill['data']['name'], 
+                                                    'name'  => $skill['data']['name'],
                                                     'passed'=> $skill['data']['passed']);
             }
         }
@@ -165,7 +162,7 @@ switch ($action) {
         if (empty($return)) {
             $success = false;
         }
-        
+
         $result = array (
             'success' => $success,
             'data' => $return
@@ -174,7 +171,7 @@ switch ($action) {
         break;
     case 'load_direct_parents':
         $id = isset($_REQUEST['id']) ? $_REQUEST['id'] : null;
-        $skills = $skill->get_direct_parents($id);        
+        $skills = $skill->get_direct_parents($id);
         $return = array();
         foreach($skills as $skill) {
             $return [$skill['data']['id']] = array (
@@ -183,26 +180,26 @@ switch ($action) {
                                                 'name'      => $skill['data']['name']
                                                 );
         }
-        echo json_encode($return);        
+        echo json_encode($return);
         break;
-    case 'profile_matches':        
+    case 'profile_matches':
         $skill_rel_user  = new SkillRelUser();
         $skills = $_REQUEST['skill_id'];
-        
+
         $total_skills_to_search = $skills;
-                
+
         $users  = $skill_rel_user->get_user_by_skills($skills);
-        
+
         $user_list = array();
-        
+
         $count_skills = count($skills);
-        
+
         if (!empty($users)) {
-            foreach ($users as $user) {            
+            foreach ($users as $user) {
                 $user_info = api_get_user_info($user['user_id']);
                 $user_list[$user['user_id']]['user'] = $user_info;
                 $my_user_skills = $skill_rel_user->get_user_skills($user['user_id']);
-                
+
                 $user_skill_list = array();
                 foreach ($my_user_skills as $skill_item) {
                     $user_skill_list[] = $skill_item['skill_id'];
@@ -210,26 +207,26 @@ switch ($action) {
 
                 $user_skills = array();
                 $found_counts = 0;
-                
+
                 foreach ($skills as $skill_id) {
                     $found = false;
                     if (in_array($skill_id, $user_skill_list)) {
                         $found = true;
                         $found_counts++;
-                        $user_skills[$skill_id] = array('skill_id' => $skill_id, 'found' => $found);                        
+                        $user_skills[$skill_id] = array('skill_id' => $skill_id, 'found' => $found);
                     }
                 }
-                
-                foreach ($my_user_skills as $my_skill) {                    
+
+                foreach ($my_user_skills as $my_skill) {
                     if (!isset($user_skills[$my_skill['skill_id']])) {
                         $user_skills[$my_skill['skill_id']] = array('skill_id' => $my_skill['skill_id'], 'found' => false);
                     }
-                    $total_skills_to_search[$my_skill['skill_id']] = $my_skill['skill_id']; 
+                    $total_skills_to_search[$my_skill['skill_id']] = $my_skill['skill_id'];
                 }
                 $user_list[$user['user_id']]['skills'] = $user_skills;
                 $user_list[$user['user_id']]['total_found_skills'] = $found_counts;
             }
-            
+
             $ordered_user_list = array();
             foreach ($user_list as $user_id => $user_data) {
                 $ordered_user_list[$user_data['total_found_skills']][] = $user_data;
@@ -239,62 +236,62 @@ switch ($action) {
                 arsort($ordered_user_list);
             }
         }
-        
-        Display::display_no_header();        
+
+        Display::display_no_header();
         Display::$global_template->assign('order_user_list', $ordered_user_list);
         Display::$global_template->assign('total_search_skills', $count_skills);
-        
+
         $skill_list = array();
 
         if (!empty($total_skills_to_search)) {
             $total_skills_to_search = $skill->get_skills_info($total_skills_to_search);
 
-            foreach ($total_skills_to_search as $skill_info) {                        
-                $skill_list[$skill_info['id']] = $skill_info;        
+            foreach ($total_skills_to_search as $skill_info) {
+                $skill_list[$skill_info['id']] = $skill_info;
             }
         }
 
         Display::$global_template->assign('skill_list', $skill_list);
-        echo Display::$global_template->fetch('default/skill/profile.tpl');        
-        break;                
+        echo Display::$global_template->fetch('default/skill/profile.tpl');
+        break;
     case 'delete_gradebook_from_skill':
     case 'remove_skill':
         if (api_is_platform_admin() || api_is_drh()) {
-            if (!empty($_REQUEST['skill_id']) && !empty($_REQUEST['gradebook_id'])) {            
-                $skill_item = $skill_gradebook->get_skill_info($_REQUEST['skill_id'], $_REQUEST['gradebook_id']);            
+            if (!empty($_REQUEST['skill_id']) && !empty($_REQUEST['gradebook_id'])) {
+                $skill_item = $skill_gradebook->get_skill_info($_REQUEST['skill_id'], $_REQUEST['gradebook_id']);
                 if (!empty($skill_item)) {
                     $skill_gradebook->delete($skill_item['id']);
                     echo 1;
                 } else {
-                    echo 0;    
+                    echo 0;
                 }
             } else {
                 echo 0;
             }
         }
-        break;             
+        break;
     case 'save_profile':
         if (api_is_platform_admin() || api_is_drh()) {
             $skill_profile = new SkillProfile();
             $params = $_REQUEST;
-            //$params['skills'] = isset($_SESSION['skills']) ? $_SESSION['skills'] : null; 
+            //$params['skills'] = isset($_SESSION['skills']) ? $_SESSION['skills'] : null;
             $params['skills'] = $params['skill_id'];
-            $skill_data = $skill_profile->save($params);        
+            $skill_data = $skill_profile->save($params);
             if (!empty($skill_data)) {
                 echo 1;
             } else {
                 echo 0;
             }
         }
-        break;        
+        break;
     case 'skill_exists':
-        $skill_data = $skill->get($_REQUEST['skill_id']);        
+        $skill_data = $skill->get($_REQUEST['skill_id']);
         if (!empty($skill_data)) {
             echo 1;
         } else {
             echo 0;
         }
-        break;   
+        break;
     default:
         echo '';
 }
diff --git a/main/inc/ajax/social.ajax.php b/main/inc/ajax/social.ajax.php
index 9fd6bcd1f1..fdd4f230bd 100644
--- a/main/inc/ajax/social.ajax.php
+++ b/main/inc/ajax/social.ajax.php
@@ -1,5 +1,5 @@
 <?php
-/* For licensing terms, see /chamilo_license.txt */
+/* For licensing terms, see /license.txt */
 /**
  * Responses to AJAX calls
  */
@@ -123,7 +123,6 @@ switch ($action) {
 			echo '';
 			break;
 		}
-		require_once api_get_path(LIBRARY_PATH).'blog.lib.php';
 		require_once api_get_path(SYS_CODE_PATH).'forum/forumfunction.inc.php';
 
 		$user_id = intval($_SESSION['social_user_id']);
diff --git a/main/inc/ajax/thematic.ajax.php b/main/inc/ajax/thematic.ajax.php
index 81ef654559..8425ea4ee3 100644
--- a/main/inc/ajax/thematic.ajax.php
+++ b/main/inc/ajax/thematic.ajax.php
@@ -1,19 +1,17 @@
 <?php
-/* For licensing terms, see /chamilo_license.txt */
+/* For licensing terms, see /license.txt */
 /**
- * Responses to AJAX calls for thematic 
+ * Responses to AJAX calls for thematic
  */
- 
+
 require_once '../global.inc.php';
-require_once api_get_path(LIBRARY_PATH).'attendance.lib.php';
-require_once api_get_path(LIBRARY_PATH).'thematic.lib.php';
 
 api_protect_course_script(true);
 
 $action = $_GET['a'];
 $thematic = new Thematic();
 
-switch ($action) {		
+switch ($action) {
 	case 'save_thematic_plan':
 		/*$title_list         = $_REQUEST['title'];
 		$description_list   = $_REQUEST['desc'];
@@ -24,51 +22,51 @@ switch ($action) {
 				$thematic->set_thematic_plan_attributes($_REQUEST['thematic_id'], $title_list[$i], $description_list[$i], $description_type[$i]);
 				$affected_rows = $thematic->thematic_plan_save();
 			}
-		}	
+		}
 		$thematic_plan_data = $thematic->get_thematic_plan_data();
 		$return = $thematic->get_thematic_plan_div($thematic_plan_data);
 		echo $return[$_REQUEST['thematic_id']];*/
-		break;        
-	case 'save_thematic_advance':		
+		break;
+	case 'save_thematic_advance':
 		if (!api_is_allowed_to_edit(null, true)) {
 			echo '';
 			exit;
         }
         /*
-		if (($_REQUEST['start_date_type'] == 1 && empty($_REQUEST['start_date_by_attendance'])) || (!empty($_REQUEST['duration_in_hours']) && !is_numeric($_REQUEST['duration_in_hours'])) ) {	    			
+		if (($_REQUEST['start_date_type'] == 1 && empty($_REQUEST['start_date_by_attendance'])) || (!empty($_REQUEST['duration_in_hours']) && !is_numeric($_REQUEST['duration_in_hours'])) ) {
 			if ($_REQUEST['start_date_type'] == 1 && empty($_REQUEST['start_date_by_attendance'])) {
         		$start_date_error = true;
-    			$data['start_date_error'] = $start_date_error;	
-			} 
-        			
+    			$data['start_date_error'] = $start_date_error;
+			}
+
         	if (!empty($_REQUEST['duration_in_hours']) && !is_numeric($_REQUEST['duration_in_hours'])) {
         		$duration_error = true;
-    			$data['duration_error'] = $duration_error;	
+    			$data['duration_error'] = $duration_error;
         	}
-    
-    		$data['action'] = $_REQUEST['action'];	
-    		$data['thematic_id'] = $_REQUEST['thematic_id'];				
-    		$data['attendance_select'] = $attendance_select;					
+
+    		$data['action'] = $_REQUEST['action'];
+    		$data['thematic_id'] = $_REQUEST['thematic_id'];
+    		$data['attendance_select'] = $attendance_select;
     		if (isset($_REQUEST['thematic_advance_id'])) {
     			$data['thematic_advance_id'] = $_REQUEST['thematic_advance_id'];
     			$thematic_advance_data = $thematic->get_thematic_advance_list($_REQUEST['thematic_advance_id']);
-    			$data['thematic_advance_data'] = $thematic_advance_data;		
-    		}	    			
-		} else {   				
-			if ($_REQUEST['thematic_advance_token'] == $_SESSION['thematic_advance_token'] && api_is_allowed_to_edit(null, true)) {    	    			
+    			$data['thematic_advance_data'] = $thematic_advance_data;
+    		}
+		} else {
+			if ($_REQUEST['thematic_advance_token'] == $_SESSION['thematic_advance_token'] && api_is_allowed_to_edit(null, true)) {
     	    	$thematic_advance_id 	= $_REQUEST['thematic_advance_id'];
-    	    	$thematic_id 			= $_REQUEST['thematic_id'];	    			
+    	    	$thematic_id 			= $_REQUEST['thematic_id'];
     	    	$content 				= $_REQUEST['real_content'];
     	    	$duration				= $_REQUEST['duration_in_hours'];
     	    	if (isset($_REQUEST['start_date_type']) && $_REQUEST['start_date_type'] == 2) {
     	    		$start_date 	= $thematic->build_datetime_from_array($_REQUEST['custom_start_date']);
-    	    		$attendance_id 	= 0;	
+    	    		$attendance_id 	= 0;
     	    	} else {
     	    		$start_date 	= $_REQUEST['start_date_by_attendance'];
     	    		$attendance_id 	= $_REQUEST['attendance_select'];
-    	    	}		    			
-    	    	$thematic->set_thematic_advance_attributes($thematic_advance_id, $thematic_id,  $attendance_id, $content, $start_date, $duration);	    				    								
-				$affected_rows = $thematic->thematic_advance_save();			        	
+    	    	}
+    	    	$thematic->set_thematic_advance_attributes($thematic_advance_id, $thematic_id,  $attendance_id, $content, $start_date, $duration);
+				$affected_rows = $thematic->thematic_advance_save();
     		    if ($affected_rows) {
     		    	// get last done thematic advance before move thematic list
     				$last_done_thematic_advance = $thematic->get_last_done_thematic_advance();
@@ -79,53 +77,53 @@ switch ($action) {
 				}
 			}
 		}
-		$thematic_advance_data = $thematic->get_thematic_advance_list(null, null, true);        
-		$return = $thematic->get_thematic_advance_div($thematic_advance_data);		
+		$thematic_advance_data = $thematic->get_thematic_advance_list(null, null, true);
+		$return = $thematic->get_thematic_advance_div($thematic_advance_data);
 		echo $return[$_REQUEST['thematic_id']][$_REQUEST['thematic_advance_id']];*/
-        break;		
-	case 'get_datetime_by_attendance':							
-		$attendance_id       = intval($_REQUEST['attendance_id']);        
+        break;
+	case 'get_datetime_by_attendance':
+		$attendance_id       = intval($_REQUEST['attendance_id']);
 		$thematic_advance_id = intval($_REQUEST['thematic_advance_id']);
-		
+
 		$label = '';
-		$input_select = '';			
+		$input_select = '';
 		if (!empty($attendance_id)) {
-			$attendance = new Attendance();										
-			$thematic   = new Thematic();                
+			$attendance = new Attendance();
+			$thematic   = new Thematic();
             $thematic_list = $thematic->get_thematic_list();
-            
+
             $my_list = $thematic_list_temp = array();
-            foreach ($thematic_list as $item) {                    	
-                $my_list = $thematic->get_thematic_advance_by_thematic_id($item['id']);                    
+            foreach ($thematic_list as $item) {
+                $my_list = $thematic->get_thematic_advance_by_thematic_id($item['id']);
                 $thematic_list_temp = array_merge($my_list, $thematic_list_temp);
-            }     
+            }
 			$new_thematic_list = array();
-		
+
 			foreach($thematic_list_temp as $item) {
 				if (!empty($item['attendance_id']) ) {
 					$new_thematic_list[$item['id']] = array('attendance_id' =>$item['attendance_id'], 'start_date'=>$item['start_date']);
 				}
-			}            
-			          
-			$attendance_calendar = $attendance->get_attendance_calendar($attendance_id);	
-            
+			}
+
+			$attendance_calendar = $attendance->get_attendance_calendar($attendance_id);
+
 			$label = get_lang('StartDate');
 			if (!empty($attendance_calendar)) {
-				$input_select .= '<select id="start_date_select_calendar" name="start_date_by_attendance" UNIQUE size="5">';				
+				$input_select .= '<select id="start_date_select_calendar" name="start_date_by_attendance" UNIQUE size="5">';
 				foreach ($attendance_calendar as $calendar) {
                     $selected = null;
 					$insert = true;
-					//checking if was already taken						
+					//checking if was already taken
 					foreach ($new_thematic_list as $key => $thematic_item) {
 						//if ($calendar['db_date_time'] == $thematic_item['start_date'] && $calendar['attendance_id'] == $thematic_item['attendance_id'] ) {
                         if ($calendar['db_date_time'] == $thematic_item['start_date'] ) {
-							$insert = false;                            
+							$insert = false;
                             if ($thematic_advance_id == $key) {
-                                $insert = true; 
+                                $insert = true;
                                 $selected = 'selected';
                             }
-							break;	
-						}						
+							break;
+						}
 					}
 					if ($insert == true) {
 						$input_select .= '<option '.$selected.' value="'.$calendar['date_time'].'">'.$calendar['date_time'].'</option>';
@@ -135,23 +133,23 @@ switch ($action) {
 			} else {
 				$input_select .= '<em>'.get_lang('ThereAreNoRegisteredDatetimeYet').'</em>';
 			}
-		} 
-		?>			
+		}
+		?>
 		<div class="control-group">
 			<label class="control-label"><?php echo $label ?></label>
 			<div class="controls"><?php echo $input_select ?></div>
-		</div>			
-		<?php				
-	    break;	    
-	case 'update_done_thematic_advance':	
+		</div>
+		<?php
+	    break;
+	case 'update_done_thematic_advance':
 		$thematic_advance_id = intval($_GET['thematic_advance_id']);
-		$total_average = 0;			
-		if (!empty($thematic_advance_id)) {				
-			$thematic = new Thematic();				
-			$affected_rows  = $thematic->update_done_thematic_advances($thematic_advance_id);			
+		$total_average = 0;
+		if (!empty($thematic_advance_id)) {
+			$thematic = new Thematic();
+			$affected_rows  = $thematic->update_done_thematic_advances($thematic_advance_id);
 			//if ($affected_rows) {
 			$total_average  = $thematic->get_total_average_of_thematic_advances(api_get_course_id(), api_get_session_id());
-			//}			
+			//}
 		}
 		echo $total_average;
 		break;
diff --git a/main/inc/ajax/timeline.ajax.php b/main/inc/ajax/timeline.ajax.php
index 2a0c269a9a..52e2babfc0 100644
--- a/main/inc/ajax/timeline.ajax.php
+++ b/main/inc/ajax/timeline.ajax.php
@@ -1,18 +1,20 @@
 <?php
+/* For licensing terms, see /license.txt */
+
 require_once '../global.inc.php';
-require_once api_get_path(LIBRARY_PATH).'timeline.lib.php';
 
 $timeline = new Timeline();
 
 $action = $_GET['a'];
 
-switch ($action) {		
+switch ($action) {
 	case 'get_timeline_content':
         $items = $timeline->get_timeline_content($_GET['id']);
-        echo json_encode($items);      
+        echo json_encode($items);
         /*echo '<pre>';
         echo json_encode($items);
         echo '</pre>';
         var_dump($items);*/
     break;
-}
\ No newline at end of file
+}
+exit;
\ No newline at end of file
diff --git a/main/inc/ajax/user_manager.ajax.php b/main/inc/ajax/user_manager.ajax.php
index 96841e9d31..e09183d3cc 100644
--- a/main/inc/ajax/user_manager.ajax.php
+++ b/main/inc/ajax/user_manager.ajax.php
@@ -1,5 +1,5 @@
 <?php
-/* For licensing terms, see /chamilo_license.txt */
+/* For licensing terms, see /license.txt */
 /**
  * Responses to AJAX calls
  */
diff --git a/main/inc/ajax/work.ajax.php b/main/inc/ajax/work.ajax.php
index c8ed111c68..e83ae86219 100644
--- a/main/inc/ajax/work.ajax.php
+++ b/main/inc/ajax/work.ajax.php
@@ -5,17 +5,13 @@
  */
 
 require_once '../global.inc.php';
-
 require_once api_get_path(SYS_CODE_PATH).'work/work.lib.php';
 
-
 $action = isset($_REQUEST['a']) ? $_REQUEST['a'] : null;
 
 switch ($action) {
-	case 'get_work_user_list':        
-       
-
-		break;	
+	case 'get_work_user_list':
+		break;
     default:
         echo '';
 }
diff --git a/main/inc/lib/link.lib.php b/main/inc/lib/link.lib.php
index 18bbe7730f..d41bd85452 100644
--- a/main/inc/lib/link.lib.php
+++ b/main/inc/lib/link.lib.php
@@ -20,7 +20,8 @@
 
 /* FUNCTIONS */
 
-class Link extends Model {
+class Link extends Model
+{
     var $table;
     var $is_course_model = true;
     var $columns = array('id', 'c_id','url','title','description','category_id', 'display_order', 'on_homepage', 'target', 'session_id');
diff --git a/main/inc/lib/main_api.lib.php b/main/inc/lib/main_api.lib.php
index 56b917603c..4ce934bc89 100644
--- a/main/inc/lib/main_api.lib.php
+++ b/main/inc/lib/main_api.lib.php
@@ -392,6 +392,11 @@ define('SOCIAL_CENTER_PLUGIN',      2);
 define('SOCIAL_RIGHT_PLUGIN',       3);
 define('CUT_GROUP_NAME', 50);
 
+//Skills
+define ('SKILL_TYPE_REQUIREMENT',   'required');
+define ('SKILL_TYPE_ACQUIRED',      'acquired');
+define ('SKILL_TYPE_BOTH',          'both');
+
 
 /* PATHS & FILES - ROUTINES */
 
diff --git a/main/inc/lib/nanogong.lib.php b/main/inc/lib/nanogong.lib.php
index 8cd7d0f430..2a676c3db9 100644
--- a/main/inc/lib/nanogong.lib.php
+++ b/main/inc/lib/nanogong.lib.php
@@ -278,7 +278,6 @@ class Nanogong
      */
     public function upload_file($is_nano = false)
     {
-        require_once api_get_path(LIBRARY_PATH).'document.lib.php';
         if (!empty($_FILES)) {
             $upload_ok = FileManager::process_uploaded_file($_FILES['file'], false);
 
diff --git a/main/inc/lib/notebook.lib.php b/main/inc/lib/notebook.lib.php
index c16cf59100..c6fdee8034 100644
--- a/main/inc/lib/notebook.lib.php
+++ b/main/inc/lib/notebook.lib.php
@@ -10,8 +10,9 @@
  */
 class NotebookManager {
 
-    private function __construct() {
-        
+    public function __construct()
+    {
+
     }
 
     /**
@@ -165,7 +166,7 @@ class NotebookManager {
             $sort_direction = 'DESC';
             $link_sort_direction = 'ASC';
         }
-        
+
         // action links
         echo '<div class="actions">';
         if (!api_is_anonymous()) {
@@ -223,6 +224,6 @@ class NotebookManager {
             echo '<a href="' . api_get_self() . '?action=editnote&amp;notebook_id=' . $row['notebook_id'] . '">' . Display::return_icon('edit.png', get_lang('Edit'), '', ICON_SIZE_SMALL) . '</a>';
             echo '<a href="' . api_get_self() . '?action=deletenote&amp;notebook_id=' . $row['notebook_id'] . '" onclick="return confirmation(\'' . $row['title'] . '\');">' . Display::return_icon('delete.png', get_lang('Delete'), '', ICON_SIZE_SMALL) . '</a>';
             echo '</div>';
-        }        
+        }
     }
 }
\ No newline at end of file
diff --git a/main/inc/lib/search/xapian/XapianIndexer.class.php b/main/inc/lib/search/xapian/XapianIndexer.class.php
index 04997a9635..22d10d93d9 100644
--- a/main/inc/lib/search/xapian/XapianIndexer.class.php
+++ b/main/inc/lib/search/xapian/XapianIndexer.class.php
@@ -72,7 +72,7 @@ abstract class XapianIndexer
         }
 
         if ($path == null) {
-            $path = api_get_path(SYS_PATH_DATA).'searchdb/';
+            $path = api_get_path(SYS_DATA_PATH).'searchdb/';
         }
         try {
             $this->db = new XapianWritableDatabase($path, $dbMode);
diff --git a/main/inc/lib/search/xapian/XapianQuery.php b/main/inc/lib/search/xapian/XapianQuery.php
index 31dfd31ae9..3a5aa2c186 100644
--- a/main/inc/lib/search/xapian/XapianQuery.php
+++ b/main/inc/lib/search/xapian/XapianQuery.php
@@ -12,7 +12,7 @@ require_once dirname(__FILE__) . '/../IndexableChunk.class.php';
 //TODO: think another way without including specific fields here
 require_once api_get_path(LIBRARY_PATH) . 'specific_fields_manager.lib.php';
 
-define('XAPIAN_DB', api_get_path(SYS_PATH_DATA) . 'data/searchdb/');
+define('XAPIAN_DB', api_get_path(SYS_DATA_PATH) . 'searchdb/');
 
 /**
  * Queries the database.
diff --git a/main/inc/lib/skill.lib.php b/main/inc/lib/skill.lib.php
index ff8c9f71af..e44dea0292 100644
--- a/main/inc/lib/skill.lib.php
+++ b/main/inc/lib/skill.lib.php
@@ -8,14 +8,10 @@
 /**
  * Code
  */
-define ('SKILL_TYPE_REQUIREMENT',   'required');
-define ('SKILL_TYPE_ACQUIRED',      'acquired');
-define ('SKILL_TYPE_BOTH',          'both');
 
-require_once api_get_path(LIBRARY_PATH).'model.lib.php';
-
-class SkillProfile extends Model {
-    var $columns = array('id', 'name', 'description');
+class SkillProfile extends Model
+{
+    public $columns = array('id', 'name', 'description');
     public function __construct() {
         $this->table = Database::get_main_table(TABLE_MAIN_SKILL_PROFILE);
         $this->table_rel_profile = Database::get_main_table(TABLE_MAIN_SKILL_REL_PROFILE);
diff --git a/main/notebook/index.php b/main/notebook/index.php
index add05c9e66..7545838541 100644
--- a/main/notebook/index.php
+++ b/main/notebook/index.php
@@ -16,8 +16,6 @@ require_once '../inc/global.inc.php';
 
 $current_course_tool  = TOOL_NOTEBOOK;
 
-require_once api_get_path(LIBRARY_PATH).'notebook.lib.php';
-
 // The section (tabs)
 $this_section = SECTION_COURSES;
 
@@ -26,7 +24,7 @@ api_protect_course_script(true);
 
 // Additional javascript
 $htmlHeadXtra[] = NotebookManager::javascript_notebook();
-$htmlHeadXtra[] = '<script type="text/javascript">
+$htmlHeadXtra[] = '<script>
 function setFocus(){
 $("#note_title").focus();
 }
diff --git a/main/reservation/rsys.php b/main/reservation/rsys.php
index 577cc9ccc2..9524f25506 100644
--- a/main/reservation/rsys.php
+++ b/main/reservation/rsys.php
@@ -1741,7 +1741,5 @@ class Rsys {
 $language_file = 'reservation';
 $cidReset = true;
 require_once '../inc/global.inc.php';
-require_once api_get_path(LIBRARY_PATH).'sortable_table.class.php';
 Rsys :: init();
-require_once 'rcalendar.php';
-require_once api_get_path(LIBRARY_PATH).'formvalidator/FormValidator.class.php';
+require_once 'rcalendar.php';
\ No newline at end of file
diff --git a/main/social/home.php b/main/social/home.php
index bf22054dcb..4ce21c3109 100644
--- a/main/social/home.php
+++ b/main/social/home.php
@@ -11,7 +11,6 @@ $language_file = array('userInfo');
 $cidReset = true;
 
 require_once '../inc/global.inc.php';
-require_once api_get_path(LIBRARY_PATH).'skill.lib.php';
 
 $user_id = api_get_user_id();
 $show_full_profile = true;
diff --git a/main/social/skills_tree.php b/main/social/skills_tree.php
index e93be3d2fd..b04ec7ab44 100644
--- a/main/social/skills_tree.php
+++ b/main/social/skills_tree.php
@@ -10,8 +10,6 @@ $language_file = array('admin');
 
 $cidReset = true;
 require_once '../inc/global.inc.php';
-require_once api_get_path(LIBRARY_PATH).'skill.lib.php';
-require_once api_get_path(LIBRARY_PATH).'skill.visualizer.lib.php';
 
 $this_section = SECTION_MYPROFILE;
 
diff --git a/main/timeline/view.php b/main/timeline/view.php
index 3a60d28ccb..49b4881e96 100644
--- a/main/timeline/view.php
+++ b/main/timeline/view.php
@@ -1,6 +1,6 @@
 <?php
 /* For licensing terms, see /license.txt */
-/**	
+/**
 	@author Julio Montoya <gugli100@gmail.com> BeezNest 2011
 *	@package chamilo.timeline
 */
@@ -9,8 +9,6 @@
 $language_file = array ('registration','admin');
 require_once '../inc/global.inc.php';
 
-require_once api_get_path(LIBRARY_PATH).'timeline.lib.php';  
-
 $interbreadcrumb[]=array('url' => 'index.php','name' => get_lang('Timeline'));
 $interbreadcrumb[]=array('url' => 'index.php','name' => get_lang('Listing'));
 
@@ -28,7 +26,7 @@ $htmlHeadXtra[] = '
 <script>
 	$(document).ready(function() {
 		var timeline = new VMM.Timeline();
-		timeline.init("'.$url.'");			
+		timeline.init("'.$url.'");
 	});
 </script>';
 $content = '<div class="timeline-example"><div id="timeline"></div></div>';
diff --git a/main/tracking/lp_results_by_user.php b/main/tracking/lp_results_by_user.php
index 2bce6329b2..2bde64ee83 100644
--- a/main/tracking/lp_results_by_user.php
+++ b/main/tracking/lp_results_by_user.php
@@ -14,7 +14,6 @@
 $language_file = array ('registration', 'index', 'tracking', 'exercice','survey');
 
 require_once '../inc/global.inc.php';
-require_once api_get_path(LIBRARY_PATH).'formvalidator/FormValidator.class.php';
 require_once api_get_path(LIBRARY_PATH).'pear/Spreadsheet_Excel_Writer/Writer.php';
 
 $this_section = SECTION_TRACKING;
diff --git a/main/tracking/question_course_report.php b/main/tracking/question_course_report.php
index 1aebdda068..26e1c76adb 100644
--- a/main/tracking/question_course_report.php
+++ b/main/tracking/question_course_report.php
@@ -12,7 +12,6 @@ require_once '../inc/global.inc.php';
 
 require_once api_get_path(SYS_CODE_PATH).'exercice/exercise.class.php';
 require_once api_get_path(SYS_CODE_PATH).'exercice/question.class.php';
-require_once api_get_path(LIBRARY_PATH).'formvalidator/FormValidator.class.php';
 require_once api_get_path(LIBRARY_PATH).'pear/Spreadsheet_Excel_Writer/Writer.php';
 
 require_once api_get_path(SYS_CODE_PATH).'newscorm/learnpathList.class.php';