diff --git a/apps/user_ldap/ajax/setConfiguration.php b/apps/user_ldap/ajax/setConfiguration.php
index 94de8835fbc..84acecee5da 100644
--- a/apps/user_ldap/ajax/setConfiguration.php
+++ b/apps/user_ldap/ajax/setConfiguration.php
@@ -27,6 +27,18 @@ OCP\JSON::checkAppEnabled('user_ldap');
 OCP\JSON::callCheck();
 
 $prefix = $_POST['ldap_serverconfig_chooser'];
+
+// Checkboxes are not submitted, when they are unchecked. Set them manually.
+// only legacy checkboxes (Advanced and Expert tab) need to be handled here,
+// the Wizard-like tabs handle it on their own
+$chkboxes = array('ldap_configuration_active', 'ldap_override_main_server',
+				  'ldap_nocase', 'ldap_turn_off_cert_check');
+foreach($chkboxes as $boxid) {
+	if(!isset($_POST[$boxid])) {
+		$_POST[$boxid] = 0;
+	}
+}
+
 $ldapWrapper = new OCA\user_ldap\lib\LDAP();
 $connection = new \OCA\user_ldap\lib\Connection($ldapWrapper, $prefix);
 $connection->setConfiguration($_POST);