Ok, so I have 3 computers in a workgroup (through router...). All three computers can ping each other and access each other's shared files with no problem, however, one of the computers, lets call it computer B, cannot ping ITSELF (it can ping 127.0.0.1, but not its IP, which i set to 192.168.2.6, or by its name). What makes this odd is that computers A and C can both ping this computer with no problem. All three have subnet masks of 255.255.255.0, gateways of 192.168.2.1. The original problem was that computers A or B were unable to see or ping each other under any circumstances, although they could both see and ping computer C with no problem. I tried resetting all the names and all on all 3 computers, and the same problem occured with computers B and C being unable to see or ping each other, but both being able to see and ping computer A. The problem was then fixed when I set a custom IP for computer B (it was unable to ping itself with an automatic IP as well). It's also possible that what helped was that I changed the socket into which I connected computer B on the router (it has space for 4, needed 3...). Could this possibly be a physical problem? or is there something i'm missing?

What OS are they running?
Is the windows firewall enabled?
What's with this pinging?

XP Pro, i disabled all firewalls...
ping? the command to send small packets of information between one system and another and get it back to check latency or for an existing connection? In this case the problem (oddly enough) is that the computer is unable to ping ITSELF =/ (which all the others are capable of doing...)