[Phalanx]

Okay, if you can can't ping them, yet they all have access to the internet then it is a firewall/router issue. Whether it's the router or some software firewall on the Windows machine I can't tell.

I would take the machines, reconnect them to the hub, connect that hub to your firewall/router. Then see if you can ping and/or tracert the machines connected to the hub. This may eliminate or confirm the firewall/router as to where the issue lays.

If all of your stations can ping and tracert each other when connected to the hub and they have access to the internet too, then issue is within the firewall/router. If not, then it is something in the configuration of the machines that can't communicate with each other.

Also some firewall/routers need to know the "workgroup" or "windows domain" that they participate in otherwise they won't allow the peer to peer networking. I'm not sure if the router you have is one of those or not.