Thread:Project:Support desk/Warning and Fatal error when running web update for 1.18

We are currently runnning MW 1.14.0 and we are trying to upgrade to 1.18.

When I go to do the web updater I get the following errors

Warning: call_user_func(Installer::overrideConfig) [function.call-user-func]: First argument is expected to be a valid callback in D:\xampp\htdocs\XXXXXXXX\includes\WebStart.php on line 101

Fatal error: Class 'WebInstaller' not found in D:\xampp\htdocs\XXXXXXXX\mw-config\index.php on line 23