I'm using XP SP 3. From time to time my browsers stop working - unable to connect to site - firefox, chrome & IE all the same. Outlook email still works can send & receive. Can ping sites. Restarting browsers does not work, have to reboot. Have another laptop on network that does not have this problem only difference laptop is wireless mine with problem is wired desktop. Starting to get really pissed off - not firewall either. Help
Try rebooting your router, modem and then both.
Try powering everything off for 10 seconds, then bring up your network in the order: