Weird Internet Explorer Messages

I have a Dell running Windows XP with Internet Explorer 6.0. Under my husbands login setting, he appears to be connected to the internet because he can download email just fine. When he gets into Internet Explorer he goes no where. He gets a "This page cannot be displayed" message on every web site he wants to go to. Sometimes he gets a "Internet Exploreer could not open the search page" message. I went to Tools/Diagnose Connection Problems and it gives me this message, "Windows has detecte a connection problem between the computer and the modem." It says to check the connections and they are all just fine. They weird thing is under my settings and my daughters settings everyhting works great. We can surf to any web page and get no trouble messages. I ran antivirus and my all my updates are current. What is going on under my husbands settings?