Halo help?

Whenever I join matchmaking, regardless of the playlist (dubs, SWAT, Lone Wolves, Actionsack) I get to the pre-game lobby and I see all the players, etc., and then after like 10 seconds it boots me out back to the matchmaking lobby. Can someone help?

Also; what gamer picture pack has the gold and silver crowns with the black backgrounds? It's just a 3 pronged crown, either gold or silver, with a black background.


Thanks,
ac1d
(aKa Nulled)

 

The only thing I can think of that might be the issue is your disc might be scratched, or your NAT might be closed/strict. There are plenty of good guides to opening your NAT in the Halo 3 section of bungie.net if you want to give it a try.