Bumping this, I can confirm that both myself, and somebody else I know are experiencing the exact same problem at the exact same time, and no solutions brought up so far (adjusting IE settings, flushing dns, release/renew, reinstall, firewall, antivirus, etc.) have helped us. We're both on Windows Vista Service Pack 2, if that helps, but I'm quite sure the only other thing to try would be a system restore.