I'm thinking that the issue has to do with how the Website redirects people. classic-space.com/forum works fine but if you just enter classic-space.com or classic-space.com/index.php it doesn't get though.
The difference is probably in whether you go directly to classic-space.com or classic-space.com/forum. The latter still worked after the redirect broke.
I made the redirect script thingy read-only, so hopefully it won't get nuked again.