Strange networking issue: pings don't work, Exchange connection drops, UNC paths still work.
Posted on 2011-04-28
This is a strange issue we are having with a single computer at one of our locations. The problem computer is in a remote office that is connected to the main office via WAN. There are dozens of other computers at the remote location that are unaffected.
The user will first notice that her connection to the Exchange server has dropped in Outlook. At this time, web traffic to external sites, as well as pings to external sites will also stop working. If she tries to ping the exchange server it will time out. Also during these periods of connectivity problems, her computer is unpingable. But this is where it gets weird: he local area connection shows a "connected" status, and if she tries connecting to a shared folder using a UNC path such as \\servername\share it will connect as if nothing were wrong.
The problem will last about 30 minutes and then fix itself. Everything will start working again. She will be able to ping outside web sites, Exchange connectivity is restored and she can ping the Exchange server, and her computer responds to pings again. UNC paths also continue to work normally.
-All event logs are clean and don't show any reasons for the problem
-All patches have been applied to the computer regularly
-All drivers are recent and up-to-date
-No other computers at her location have this problem, and are identical to hers with regard to hardware, drivers, and OS
Any thoughts on where to look at solving this one?