I bought the Xbox One Halo MCC bundle about 2 weeks ago.
I'm having all sorts of off-and-on problems joining games.
The only solution I've found that seems to work is to start another game - let it load completely - then go back and start Halo and it seems to reset anything.
It starts downloading "Latest Matchmaking Data" and never finishes.
If I have played a game and then leave the room for a while - when I come back it will say "Active Profile signed out" and not let me join a matchmaking game.
Sometimes it will say it is not connected to Xbox Live but I do a connection test and everything works fine.
Sometimes it says the Settings do not allow me to join a multiplayer game.
I cannot figure out any rhyme or reason as to which error I get when... like I said the only solution I know of is to start another game, sometimes I shut down the xbox and wait a while and start it back up and it will join a game..
What is the fix for this?