If your wordpress site appeared this error: There has been a critical error on your website, this tutorial will help you how to find the reason and fix it.
There has been a critical error on your website error may like this:
In order to fix it, you shoud open your wp-config.php file of wordpress.
You can use FileZilla to connect your site and open wp-config.php, then add or edit code below in this file.
define( 'SCRIPT_DEBUG', true );
Then we can enable wordpress debug model.
You open your site again, wordpress will show you the reason why this error occur. You can find the reason and fix it.