Ticket #2392 - Point №1: Related fix.

modules/boonex/timeline/classes/BxTimelineModule.php

@@ -2820,7 +2820,7 @@ class BxTimelineModule extends BxBaseModNotificationsModule implements iBxDolCon
             return CHECK_ACTION_RESULT_ALLOWED;
 
         // check ACL
-        if(($oOwner = BxDolProfile::getInstanceMagic($iOwnerId)) !== false) {
+        if($iOwnerId != 0 && ($oOwner = BxDolProfile::getInstanceMagic($iOwnerId)) !== false) {
             $mixedCheckResult = BxDolService::call($oOwner->getModule(), 'check_allowed_with_content_for_profile', array('view', $oOwner->getContentId(), $iProfileId));
             if($mixedCheckResult !== CHECK_ACTION_RESULT_ALLOWED)
                 return $mixedCheckResult;