Xbox One X not downloading profile for 360 games

All Microsoft Xbox accounts have an Xbox 360 profile that can be downloaded to either a real Xbox 360 console or to the Xbox 360 emulated dashboard on Xbox One and Series X|S consoles. Even if you made a new account now, it would still have a 360 profile.

When you run a backwards compatible 360 game on your Series X for the first time, you will be asked to enter your email address and password. This is so the 360 profile can be downloaded. It does this because that is how the Xbox 360 does things.

Xbox Support was able to fix my profile. I'm now able to successfully download and sign into my Xbox 360 profile on my Xbox One X.

Xbox 360 games do not appear to see these users and I'm unable to select them when adding players to 360-games.

User accounts work differently on the 360 (and the 360 emulator on the Xbox One and Series X/S) to the way they do on Xbox One and Series X/S. The 360 had user profiles that needed to be downloaded first.

It's been a while so you'll need to bear with me. If remember you will need to sign in first with this other user you've created, then launch the 360 game. This will download the additional new profile to the console. I think, after this you should be able
to add this player to your game.

Hi, re-downloading your Xbox 360 profile can sometimes fix issues like this. To do so, just start a xbox 360 game, go into the xbox 360 guide, and select x to sign out, then select downlod profile, then follow the instuctions to re-download your profile.

Enter the game, press the smallest buttons on the controller at the same time (Accessibility and Start), this will open the Xbox 360 interface, log out by pressing X.

That done, restart the game and go to the Xbox 360 interface, choose Download Profile and download your profile again.