can't co-op in invite only sessions with friends

The Servers have to be down or at least the Co-op Cause I Still can't find my brothers sign or join session in progress and can't even invite to game

same here.. can't play friends on co-op .. WTF? Invites don't come through. And when they do the connection for co-op fails.

Yes, there is co-op over Live, but I don't believe it's matchmade. If you want to do the co-op, you have to invite your own friends to do it. If your friends don't own the game, you can't do co-op.

Me and a friend of mine manage to play co-op successfully a few days ago, Now we can't even play at all... Am I the only one who thinks that it is a massive step-back that we both have to be in the same party in order to invite someone? What happened to
high lighting a player and pressing "join session in progress"? That system worked perfectly... Don't fix what is not broken MS.

Altair, hopefully you both have the latest updates as I know that DR2 had at least 1 if not more, so assuming that you do give this a try - hit the home button (center of the xbox controller) and go to the friends menu. Find your friend and hit "Join Session
In Progress" while he is playing, of course one of you has to answer the call and just to be safe set both of your preferences in game to "friends only". To do this go to Options>Gameplay>Co-op Privacy, and you can choose the mode of Co-op you want.

Public: You are open to anyone online joining your game. (You will have the option of accepting the request or not via in-game Transceiver message).

Private: No one may join your game session.

Friends Only: Only someone on your friends list will be able to join your session.

If all else fails, start a party and invite party to game.

I hope this helps!