At the bottom of the page, just under the bottom banner, you'll see a label showing the current server you are on (Mine currently says "Web22", for instance). Can you check which server you start on as well as which server you get the error on? The other issue that may be causing the problem is: do you have any anti-virus or anti-spam add-ins in your browser or on your system? What about your firewall?
cheers, Chris Maunder The Code Project | Co-founder Microsoft C++ MVP