So I've had a few issues recently connecting to games via XBOX live. This of course is no fun at all, especially when you want to play instead of troubleshoot networking issues.
Hopefully this post will help out.
My issue was, I was able to connect to XBOX live, and see my friends, and the games they were trying to host, then for some reason, when I attempted to connect to the game I would get "The game is no longer available".
Struggling and surfing the net for a while, I found that opening port 3074 (UDP) and pointing it to your XBOX will fix this issue.
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