Fatal error: Uncaught Error: Call to a member function getVersionString() on null in /home/u164926279/domains/qau.edu.ye/public_html/journal/lib/pkp/classes/core/PKPApplication.php:248 Stack trace: #0 /home/u164926279/domains/qau.edu.ye/public_html/journal/classes/core/Application.php(47): PKP\core\PKPApplication->__construct() #1 /home/u164926279/domains/qau.edu.ye/public_html/journal/lib/pkp/includes/bootstrap.php(37): APP\core\Application->__construct() #2 /home/u164926279/domains/qau.edu.ye/public_html/journal/index.php(18): require_once('/home/u16492627...') #3 {main} thrown in /home/u164926279/domains/qau.edu.ye/public_html/journal/lib/pkp/classes/core/PKPApplication.php on line 248

Fatal error: Uncaught Error: Call to a member function getContext() on null in /home/u164926279/domains/qau.edu.ye/public_html/journal/lib/pkp/classes/core/PKPApplication.php:496 Stack trace: #0 /home/u164926279/domains/qau.edu.ye/public_html/journal/lib/pkp/classes/plugins/PluginRegistry.php(238): PKP\core\PKPApplication->getEnabledProducts() #1 /home/u164926279/domains/qau.edu.ye/public_html/journal/lib/pkp/classes/plugins/PluginRegistry.php(127): PKP\plugins\PluginRegistry::loadFromDatabase() #2 /home/u164926279/domains/qau.edu.ye/public_html/journal/lib/pkp/classes/plugins/PluginRegistry.php(194): PKP\plugins\PluginRegistry::loadCategory() #3 [internal function]: PKP\plugins\PluginRegistry::{closure:PKP\plugins\PluginRegistry::loadAllPlugins():194}() #4 /home/u164926279/domains/qau.edu.ye/public_html/journal/lib/pkp/classes/plugins/PluginRegistry.php(194): array_reduce() #5 /home/u164926279/domains/qau.edu.ye/public_html/journal/lib/pkp/classes/scheduledTask/PKPScheduler.php(129): PKP\plugins\PluginRegistry::loadAllPlugins() #6 /home/u164926279/domains/qau.edu.ye/public_html/journal/lib/pkp/classes/core/ScheduleServiceProvider.php(87): PKP\scheduledTask\PKPScheduler->registerPluginSchedules() #7 [internal function]: PKP\core\ScheduleServiceProvider->{closure:PKP\core\ScheduleServiceProvider::boot():61}() #8 {main} thrown in /home/u164926279/domains/qau.edu.ye/public_html/journal/lib/pkp/classes/core/PKPApplication.php on line 496