1. How are you two trying to pair up? (i.e. you invite him, he invites you, you try to join each other via the profile page, you try to join each other's game using the in-game menu, etc.)
2. Are either of you able to play matchmaking while not partied up? If so, who has the longest wait time to find a match usually?
3. Do you guys have each other's accounts on each other's Xbox's? (I know it's an odd question, but it has happened...)
4. Are either of you (or both of you) in the Microsoft Preview Program?
5. What error messages (if any) do you get when you can't join him?
We have tried all of the above. Joining, or using an invite from myself or from him. We can both play on our own or with other people or in the same party if someone else has host. We do not have each other's accounts on our xboxs. Neither of us use that. It just says error connecting to game session, please try again.
We both have an open Nat.
Lastly, for whatever reason yesterday we were able to join eachother and play for a few hours. When we both get on today it does not work again. I honestly have no idea what is going on. Thank you for trying to help.