1 xpp machine loses con to router after a few minutes

20 workstations- xp pro, 1 main server- server 2k3, all behind a hardware firewall configured with NAT and acl's, all other pcs not having a problem at all, just this 1 workstation. I got the call that he lost email and access to the files on the server, he didnt have internet either, i tried "repair" and couldnt renew ip addy, so i set static with a free one in the range of the dhcp server, default gateway etc. , still nothing, re-booted the pc, all came back and worked fine with the static ip- till i walked away. He opened his outlook, opened his folder on the server, made some ajustments to a file in that folder and saved it, thats when all was dropped, and had to repeat the whole process- which worked but not very productive and he cant save the changes to the file. when its down- can not ping the router or any other pc including the server, reboot and all works fine!

 

That's strange behaviour in that a configuration works and then stops working. With networks things usually work or they don't. Situations when system sometimes work and then sometimes don't are less common. Intermittent problems like those you describe usually point to three possible causes: virus, network card problem, faulty cable.

I'd start with the easiest - swap his network cable, patch lead at the switch and even port this user is connected to at your switch.

Then update anti-virus and do a full scan. It might also be worth looking for misbehaving spy-ware.

Then I'd look at the possible network card problems. Easiest thing to start with is auto-negotiation. This can be tempremental. So try setting the connection speed and duplex manually at the network card (if you have a 100 base T switch set the network card to 100Mb/s full duplex. If the PC is connected to a 100 base T hub set the network card to 100Mb/s half duplex). If that doesn't work try dropping the speed to 10Mb/s and see if that fixes the problem. If still stuck try another network card.