Ok, I'm having trouble system linking the 4 Xboxes that I have (1 360, and 3 originals). My network setup is kind of complicated. All network devices have static IPs. I have two xboxes and a PC in one room all connected to a hub. These 2 boxes can system link with each other fine. The PC has a wireless card, and a wired ethernet card, which is connected to the hub. The wireless card is connected to a wireless router in the other room, which is what the other two xboxes (360 and original) are connected to. Again, these two can system link fine with each other. However, the two sets cannot system link with each other. In Halo, and Halo 2, I can see a game being hosted from a console in the other room, but when I try to join, it gives me an error. Actually, now I can't even see the games from the different sets. It gets even more puzzling with the fact that if I move the 360 and connect it to the hub, I can connect to and play games over Xbox live perfectly. I think the issue has something to do with my computer, but I can't figure it out. In the near future, I will be redoing my network, but until then, it would be nice if I could get this to work. I've tried the very few tips that exist for doing this, but none of them work. Can someone help?

try enabling UPnP or making the PC the Gateway of your network and then they should all be able to communicate with each other.