If you are playing on the Microsoft Store version of Age of Empires: Definitive Edition, there are a few troubleshooting steps you can take:
- Make sure you are signed in to Xbox Live before launching the game.
- If you signed in to any other PC’s with the same account, make sure you’ve signed out before playing the game on a new PC.
- Launch the Xbox App prior to launching the game. Make sure you are able to sign in to the App before launching the game.
- Try signing in over at account.xbox.com/. If you are unable to sign in, contact Xbox Live support.
If may be that you’ve already expanded the Multiplayer menu without knowing. If you can see the Lobby Browser, Quickmatch, Create Game, and Leaderboard buttons, the menu is already open!