Server crashing…

What could the possibly be causing our server to crash when I go to http://www.cnet.com? I can go anywhere else on the net just fine. We are running a MAC server with Webstar for our server and Viacomsoft for the Intranet server. We are also runningCyberNOT on Viacomsoft. I used to be able to go to CNET all the time, but now can’t even go to their home page.