Fatal error: Uncaught Error: Undefined constant "PKP\core\INDEX_FILE_LOCATION" in C:\xampp\htdocs\ojs\lib\pkp\classes\core\Core.php:46 Stack trace: #0 C:\xampp\htdocs\ojs\lib\pkp\classes\core\Core.php(31): PKP\core\Core::getBaseDir() #1 {main} thrown in C:\xampp\htdocs\ojs\lib\pkp\classes\core\Core.php on line 46