PHP message: PHP Fatal error: Class ‘WP_List_Table’ not found in
You may see this error in WordPress while disabled some plugin, because they plugin is need to use the WP_List_Table class from the WordPress.
Solving the problem
Add this to any of your activated plugin the it will load the class if it is not loaded.
if(!class_exists('WP_List_Table')) :
require_once(ABSPATH . 'wp-admin/includes/class-wp-list-table.php');
endif;