On our forum we often have trouble makers that register, flame, bait, troll etc and ultimately get banned. They then re-register and the process goes around and around.

So far most of these users are coming from AOL and when I validate their signup IP I get many legitimate members as well.

I know this is due to AOL caching/Proxy and I'd like to force the user, at least on the signup/login portion to not allow the AOL proxy/cache to be used.

Information about AOL Proxy here.

Is it possible to do this with UBB? I notice that AOL's cache/proxy servers do not read HTML so it isn't a simple matter of putting a bit of META tag in the headers.

I wound up just blocking AOL from even registering on our board

I had considered that, but we do have a fair number of AOL users and even three of our moderators use AOL over in the UK.

I can understand that. What I did did not affect any existing users or staff, just new ones from registering.