diff --git a/lib/modules/CoreParticipants.class.php b/lib/modules/CoreParticipants.class.php
index 14c885b816bc67366ba4e06f631b4e0c6419434f..b2f19485bbb35a2de6b295b2209d006dc58b052f 100644
--- a/lib/modules/CoreParticipants.class.php
+++ b/lib/modules/CoreParticipants.class.php
@@ -16,6 +16,10 @@ class CoreParticipants extends CorePlugin implements StudipModule
      */
     public function getIconNavigation($course_id, $last_visit, $user_id)
     {
+        if ($user_id === 'nobody') {
+            return null;
+        }
+
         $auto_insert_perm = Config::get()->AUTO_INSERT_SEM_PARTICIPANTS_VIEW_PERM;
         // show the participants-icon only if the course is not an auto-insert-sem
         if (
@@ -122,6 +126,10 @@ class CoreParticipants extends CorePlugin implements StudipModule
      */
     public function getTabNavigation($course_id)
     {
+        if ($GLOBALS['user']->id === 'nobody') {
+            return [];
+        }
+
         $navigation = new Navigation(_('Teilnehmende'));
         $navigation->setImage(Icon::create('persons', Icon::ROLE_INFO_ALT));
         $navigation->setActiveImage(Icon::create('persons', Icon::ROLE_INFO));
diff --git a/lib/modules/GradebookModule.class.php b/lib/modules/GradebookModule.class.php
index f459f106c4e9d5f017f8062cc6f007c3f8c2468b..6c000a74971a897082b3555beab294356e33bf88 100644
--- a/lib/modules/GradebookModule.class.php
+++ b/lib/modules/GradebookModule.class.php
@@ -45,6 +45,10 @@ class GradebookModule extends CorePlugin implements SystemPlugin, StudipModule
      */
     public function getIconNavigation($courseId, $lastVisit, $userId)
     {
+        if ($userId === 'nobody') {
+            return null;
+        }
+
         $title = _('Gradebook');
         if ($GLOBALS['perm']->have_studip_perm('tutor', $courseId, $userId)) {
             $changed = Instance::countBySQL(
diff --git a/lib/modules/LtiToolModule.class.php b/lib/modules/LtiToolModule.class.php
index eac2768184b099be8f6a5119c29147366e924b15..033f5e80c8b580edf0a6ee106e1c70021394f0e6 100644
--- a/lib/modules/LtiToolModule.class.php
+++ b/lib/modules/LtiToolModule.class.php
@@ -37,6 +37,10 @@ class LtiToolModule extends CorePlugin implements StudipModule, SystemPlugin, Pr
      */
     public function getIconNavigation($course_id, $last_visit, $user_id)
     {
+        if ($user_id === 'nobody') {
+            return null;
+        }
+
         $title = CourseConfig::get($course_id)->LTI_TOOL_TITLE;
         $changed = LtiData::countBySQL('course_id = ? AND chdate > ?', [$course_id, $last_visit]);