Re: Error Code 721 and 524
@landenxavier- I am not an Xbox one X owner but have been in the insider program. Be cautious of any pre release updates, they can cause havoc. My Xbox one was bricked by the last update (not immediately - the update was successful but my problem appeared about a day later) and the only way I could recover was to do a full factory reset which meant I had to redo all profiles, permissions etc and reinstall all games on the internal disk. The only saviour was Xbox live saves which synced so I didn't lose my game settings. I then went to insider hub and removed my console in settings. I will now only get official and tested updates. If you have an external HD then I would copy all games from internal to that for safety.
If you suspect the last Xbox update was the problem go to this link https://support.xbox.com/en-US/xbox-one/console/system-updates-solution.