VBulletin

Administration

Turn on the debug mode

Open the includes/config.php file and add the following code on a new line below <?php

$config['Misc']['debug'] = true;

Note: You should not turn on debug mode in a live environment.

Disable plugins and hooks

Open the includes/config.php file and add the following code on a new line below <?php

define('DISABLE_HOOKS', true);

Note: This is a good way to check if problems on a forum is caused by plugins