Fatal error: Uncaught Error: Call to undefined function add_filter() in C:\xampp\websites\www.aaronhui.ca\htdocs\wp-config.php:22 Stack trace: #0 C:\xampp\websites\www.aaronhui.ca\htdocs\wp-load.php(50): require_once() #1 C:\xampp\websites\www.aaronhui.ca\htdocs\wp-blog-header.php(13): require_once('C:\\xampp\\websit...') #2 C:\xampp\websites\www.aaronhui.ca\htdocs\index.php(17): require('C:\\xampp\\websit...') #3 {main} thrown in C:\xampp\websites\www.aaronhui.ca\htdocs\wp-config.php on line 22