his FF client is not showing any error (blank window) and his IE client is not showing a specific error, just a generic "unable to connect". at the bottom of the IE window it mentions a possible DNS problem (he sent me screen shots of both)
he's tried to connect from 3 machines on 3 different ISP's from what he told me. obviously he cannot PM you if he can't connect. if you provide an email address, i'll send that to him.
if you read my post above, i already instructed him to dump both his browser and DNS cache, so it's not a cache issue.