diff --git a/public/main/group/group.php b/public/main/group/group.php
index ef16868feaf..85c306341fc 100644
--- a/public/main/group/group.php
+++ b/public/main/group/group.php
@@ -234,12 +234,13 @@
 
 /*  List all categories */
 if ('true' === api_get_setting('allow_group_categories')) {
-    $defaultCategory = [
-        'iid' => null,
-        'description' => '',
-        'title' => get_lang('Default groups'),
-    ];
-    $categories = array_merge([$defaultCategory], $categories);
+    if (empty($categories)) {
+        $defaultCategoryId = GroupManager::create_category(
+            get_lang('Default groups')
+        );
+        $defaultCategory = GroupManager::get_category($defaultCategoryId);
+        $categories = [$defaultCategory];
+    }
     $course = api_get_course_entity();
     foreach ($categories as $index => $category) {
         $categoryId = $category['iid'];
@@ -264,13 +265,15 @@
             // Edit
             $actions .= '<a
                 href="group_category.php?'.api_get_cidreq().'&id='.$categoryId.'" title="'.get_lang('Edit').'">'.
-                Display::getMdiIcon('edit', 'ch-tool-icon', null, ICON_SIZE_SMALL, get_lang('Edit this category')).'</a>';
+                Display::getMdiIcon('pencil', 'ch-tool-icon', null, ICON_SIZE_SMALL, get_lang('Edit this category')).'</a>';
 
             // Delete
             $actions .= Display::url(
-                Display::getMdiIcon(ActionIcon::DELETE, 'ch-tool-icon', null, ICON_SIZE_SMALL, get_lang('Delete')),
+                Display::getMdiIcon(ActionIcon::DELETE, count($categories) == 1 ? 'ch-tool-icon-disabled' : 'ch-tool-icon', null, ICON_SIZE_SMALL, get_lang('Delete')),
                 'group.php?'.api_get_cidreq().'&action=delete_category&category_id='.$categoryId,
-                [
+                count($categories) == 1 ? [
+                    'onclick' => 'javascript:alert('."'".addslashes(api_htmlentities(get_lang('You cannot delete the last category'), ENT_QUOTES))."'".'); return false;',
+                ] : [
                     'onclick' => 'javascript:if(!confirm('."'".addslashes(api_htmlentities(get_lang('Please confirm your choice'), ENT_QUOTES))."'".')) return false;',
                 ]
             );
diff --git a/public/main/group/group_category.php b/public/main/group/group_category.php
index 9fe24a037b2..9a2fe4d70b6 100644
--- a/public/main/group/group_category.php
+++ b/public/main/group/group_category.php
@@ -103,7 +103,11 @@ function check_groups_per_user($value)
 } else {
     // Create a new category
     $action = 'add_category';
-    $form = new FormValidator('group_category');
+    $form = new FormValidator(
+        'group_category',
+        'post',
+        api_get_self().'?'.api_get_cidreq()
+    );
 }
 
 $form->addElement('header', $nameTools);
@@ -436,7 +440,7 @@ function check_groups_per_user($value)
 // Else display the form
 Display::display_header($nameTools, 'Group');
 
-$actions = '<a href="group.php">'.
+$actions = '<a href="group.php?'.api_get_cidreq().'">'.
     Display::getMdiIcon(ActionIcon::BACK, 'ch-tool-icon', null, ICON_SIZE_MEDIUM, get_lang('Back to Groups list')).'</a>';
 echo Display::toolbarAction('toolbar', [$actions]);
 
diff --git a/public/main/inc/lib/groupmanager.lib.php b/public/main/inc/lib/groupmanager.lib.php
index dc3709cd11f..4c9f42c94f8 100644
--- a/public/main/inc/lib/groupmanager.lib.php
+++ b/public/main/inc/lib/groupmanager.lib.php
@@ -889,13 +889,13 @@ public static function delete_category($cat_id, $course_code = '')
      */
     public static function create_category(
         $title,
-        $description,
-        $docState,
-        $workState,
-        $calendarState,
-        $anonuncementState,
-        $forumState,
-        $wikiState,
+        $description = '',
+        $docState = 1,
+        $workState = 1,
+        $calendarState = 1,
+        $anonuncementState = 1,
+        $forumState = 1,
+        $wikiState = 1,
         $chatState = 1,
         $selfRegistrationAllowed = 0,
         $selfUnRegistrationAllowed = 0,