Fatal error: Uncaught Error: Call to undefined function add_action() in C:\xampp\htdocs\wordpress\wp-content\pluginsBK\bluecounterwidget\blueCounterWidget.php:26 Stack trace: #0 C:\xampp\htdocs\wordpress\wp-content\pluginsBK\bluecounterwidget\blueCounterWidget.php(18): BlueCounterWidget->initialize() #1 C:\xampp\htdocs\wordpress\wp-content\pluginsBK\bluecounterwidget\blueCounterWidget.php(164): BlueCounterWidget->__construct() #2 {main} thrown in C:\xampp\htdocs\wordpress\wp-content\pluginsBK\bluecounterwidget\blueCounterWidget.php on line 26