We're excited to announce that we've fully migrated the Xbox Forums to their new home, here on the Microsoft Community forums!
As of today, going to forums.xbox.com will redirect you here to the Xbox area of the Community forums. We've moved all of your existing threads over so you can continue and start conversations with the new forums experience.
We sincerely appreciate the feedback you have provided over this transition and can't wait for you to check out the new Xbox Forums!
I have the same problem too. Annoying to say the least. My NAT is Open. I even restarted my modem and router, but that doesn't even seem to work. Any other game finds games instantly. The other 360 in the house can find games just fine without any problem.
But his 360 has a freezing issue in between menus, where-as mine doesn't.