Ok I have had this game since before injection came out. So I have a majority of the add on's and some people I know just started playing the game. They picked up Race Injection as well. So it went on and on, I could start a room up and I have the port opened but nobody could get into the races I was trying to set up. We have the same cars and tracks so that is not the problem. Tonight we tried something, I opened a room up with a car and track that came with just Race 07. It worked, everybody was able to get in and play. The problem is if it's a track or car that I have from a add on pack that they have with Injection they can't get into my room. So it seems like the game is seeing the car and track from my pack and saying the other people's car and track are from Injection so then it does not work. Am I right in assuming that it's not working because they got the cars and track from Injection and I got them from whatever original pack they came from is causing the problem? Is there a way around this so I can host a race for my friends and actually race with them with cars outside the original Race 07?