cant connect

My son's computer stopped working all of a sudden. Keeps getting "page cannot be displayed" im running windows 2000 on it and i've checked the internet options, tcpip property settings, made sure the ethernet adapter is sending and recieving and everything checks out. that i know nothing has changed. now if i a go into the cmd prompt and try to ping an address i get a reply 4 times.

 

internet explorer and firefox neither one connects...also my yahoo messenger or msn messenger wont connect either

 

My first approach would be to check it still doesn't connect using, say, Portable Firefox from a USB stick - I've known cases where the installed browser can't access the 'net but a Portable Apps one can.

Then I'd check the virus scanner - disable it and try; I had a friend's PC recently lose contact with the net - turned out to be the virus scanner had got its twisters in a knick (the license was due to expire shortly, so I took the easy option to uninstall it completely and install a new one).

My $0.02.