One-by-one over the course of almost 2 months, five of our PCs have stopped being able to connect to our file server via UNC or even ping it (neither by IP or name.)
The reverse is also true, the server is not able to open shares on or ping these PCs. They can connect to and ping any other server without a problem. The server has no problem connecting to other PCs or servers either.
The PCs are not all the same model. Four run XP Pro, one ran XP Media Center but is now running XP Pro. The server is Server 2003 Appliance Edition.
I tried unjoining two from the domain, but the same problem persisted before and after rejoining them. I tried moving them to a different location in the building, with no better luck. I also tried editing the hosts file, reinstalling the NIC drivers, pushing images onto some them, formatting and reinstalling Windows on others. The problem persisted.
One of the PCs is a laptop. On this one I was able to connect it via WiFi only and did finally manage to connect to the server that way, but when connected by Ethernet only it still fails.
When I check Address Leases in DHCP I dont see any duplicate MAC addresses and there doesnt seem to be an IP conflict.
I am out of ideas, please help.