I suspect it has to do with how the ad performs in your local machine.

Are you using IE? Are you running IEPro (IE) or ....... Plus (Firefox)? When I see "the webpage cannot be found/loaded" type of messages, it usually is because my adblocking softwares stop/prevent ad.

See this thread for similar problem/issue (re FT ad), even though you don't run into FT crash problem. Or one of your plug-ins needs to be udpated.