Fatal error: Uncaught Error: Undefined constant "PKP\scheduledTask\PKP_STRICT_MODE" in C:\xampp\htdocs\ojs\lib\pkp\classes\scheduledTask\ScheduledTaskHelper.php:320 Stack trace: #0 {main} thrown in C:\xampp\htdocs\ojs\lib\pkp\classes\scheduledTask\ScheduledTaskHelper.php on line 320