4.2.2 PL1 to PL2 Error

[Black Snow]

I have just upgraded the forum from 4.2.2 PL1 to PL2 and now I can't get the forum to work.

I get this error on every page in the admincp:

Warning: require_once(/XXX/forum/includes/adminfunctions_template.php): failed to open stream: No such file or directory in /XXX/forum/admincp/plugin.php on line 29 Fatal error: require_once(): Failed opening required '/XXX/forum/includes/adminfunctions_template.php' (include_path='.:') in /XXX/forum/admincp/plugin.php on line 29

I have disabled the plugins via config.php using this:

define("DISABLE_HOOKS", 1);

But it still won't let me in.

Any ideas?