with a guess.
Perhaps you've been hit by malware. Open IE and goto Tools > Internet Options, then the Connections tab. Click the "LAN Settings" button to open a new window. If there are any entries in there, and you do not use a Proxy server, clear all the entries and click OK/Apply/OK.
Sometimes malware will attempt to set up a Proxy Server and this will stop any internet connection.
Does that work?
Mark
I was on the internet with a few tabs open and then went to new site and got server error, could continue to work in open tabs but when I closed them I couldnt get back on the internet at all. (I have been having the occassional problem with a tab not opening but when I would reboot it would work then so never went to network connection) I went to network connections and got DNS domain name server windows failed to find the well known host "www.microsoft.com" using DNS. The server may be down. Now I can't get on internet at all. I tried IE8 & Firefox both got errors. How to know where problem is? Steps to figure it out. Any suggestions? I have windows vista and AT&T dsl (lite), 1wire modem. It may take me a while for me to get back since I now can only get internet at work.

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