Forum Getting 404 error when using Email Activation Codes from Admin CP
 

I keep getting the following error in vb 4.0.5 when using the "Quick User Links: Email Activation Codes" in the user's profile in the Admin CP:

Quote:
Forbidden

You don't have permission to access /forums/register.php on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

I tested the email in the Maintenance -> Diagnostics and it is working fine there. Does anyone have any idea what is causing this?