Windows 98 Networking

I have a 3 computer home network connected to a cable router for internet access. 1 computer has Windows 2000 and the other 2 are Win98. The Windows 2000 and 1 of the windows 98 computers can see each other in Network Neighborhood but the other 98 pc cannot. All the computers have shared folders on them. The pc that cannot see the other 2 can ping them from the command prompt by name and ip address. They all connect to the internet ok and connect to each other fine except for the 1 computer. I have tried ewverything. The 2 windows 98 computers are configured exactly the same yet the one cannot see the others. HELP!!! This is driving me nuts.