Fatal error: Uncaught Error: Undefined constant "PKP\notification\PKP_STRICT_MODE" in C:\xampp\htdocs\ojs\lib\pkp\classes\notification\INotificationInfoProvider.php:105 Stack trace: #0 {main} thrown in C:\xampp\htdocs\ojs\lib\pkp\classes\notification\INotificationInfoProvider.php on line 105