[@_ck_ Participant 16 years, 1 month ago]

My very first guess would be a problem with the way subdomains are being handled. Is it a true subdomain or a mod_rewrite subdomain?

There may be parent direct htaccess rules that is messing something up with a conflict.

It doesn’t even feel like bbPress is getting to execute, index.php is not even being called.

You’re not using multiviews correct?