Question : Can ping but not browse

Ive been finding recently alot of pc's not being able to browse sites or retrieve email. All running xp. Ive checked browser settings and all are fine. Im able to ping sites e.e google.com but not able to browse with ie or firefox. Ive tried using the winsock fix but this doesnt resolve either. The only way ive found to resolve the issue is to format/reinstall. Simply reinstalling wont resolve.

Can anyone shed any light or suggest anything to help?

Thanks in advance

Answer : Can ping but not browse

Sounds more like a router issue or firewall issue.  Do you have anytype of network filtering?  First thing to check do nslookup cnn.com on a machine from a command prompt.  Then if you get a bunch of reponses, do a telenet to one of the ip addresses like this  TELNET xxx.xxx.xxx.xxx 80  

See if you get a blank screen or just a can't connect.. if you get anything other than can't connect then you are connecting and it's something else, if you get can't connect something is blocking you from getting to that website on port 80 and you probably need to look at filtering devices software other than that machine.. if the machine gets can't connect then you probably need to start looking at internet security software on the machine.