Fatal error: Uncaught Error: Class "PKP\notification\NotificationManagerDelegate" not found in C:\xampp\htdocs\ojs\lib\pkp\classes\notification\managerDelegate\QueryNotificationManager.php:30 Stack trace: #0 {main} thrown in C:\xampp\htdocs\ojs\lib\pkp\classes\notification\managerDelegate\QueryNotificationManager.php on line 30