We have a small office of 12 users. Most of the PC's are XP but we have 2 Win 7. We're having a random problem for the XP workstations at random times they open a browser (IE, Firefox doesn't seem to matter) and try to go to any website and it says page cannot be displayed. I'm never there when it happens and it always seems to work when I go out there. The problem what ever it is seems to go away after a min or they close and open the broswer a few times. When this happens their Outlook and server loaded apps still run so it doesn't appear to be a server or network H/W problem like a switch port. Its at random times so nothing else running seems to be causing it the ISP checked their equipment and the Win 7 users so far have been uneffected. How can I troubleshoot a random problem like this?