Here is the story.
We have one xbox 360 and have really been getting into the Left 4 Dead series. We decided to get a second one so we could play with all four of us via system link. The game was already installed on xbox #1 (the older, white one). I bought the Slim 4gb xbox (xbox #2) and another copy of L4D2 yesterday. Then we connected both xbox's with an ethernet cable.
From the L4D2 main menu we went to versus -> play with friends -> create game (on xbox #2).
On xbox #1, we went to versus -> play with friends and could see the lobby on #2.
But when we tried to join, we got the error "Disconnected: Session no longer available."
It is obviously passing data back and forth over a standard ethernet cable, so I can only assume it is auto-sensing and a crossover cable isn't necessary. So I did some googling and found out that it might be a storage concern and the 4.4gb game might need to be installed to play this way. So I picked up the 320gb drive today. I added that to xbox #2 and installed L4D2 on it, and we still got the same error.
So then I wondered if it was a version error between both games even though I don't remember either of them being patched at any time. I deleted everything L4D2 off of both machines and reinstalled. And I still get the same error.
I don't get it. The only physical layer equipment between the 2 machines is a CAT5 cable. The latency is probably about nil. The two machines are obviously talking as I can see any lobby created on the other machine, but it won't let me join it.
Unfortunately, this is the only game we have a duplicate of, so I can only test with it. I don't get it... Is there something I am missing?