Since it's happening with multiple browsers and the connection itself is known to be good, I'd head directly for the bottle ofWinsock Fix, which should restore internet connectivity. I'd also run an AV and spyware scan, just in case this is all caused by malware.
Hope this helps,
When I log on to the Internet, the PC stays connected for about ten minutes, then sends messages that it "failed to find" the nominated sites. I use Firefox, and have tried uninstalling & reinstalling that, but there is no difference.Problem happens with IE too. I also occasionally run another PC on same modem,(not at the same time),and there's no problem with that one, so problem is not connection or modem.
Both P.C's use XP SP2.