AppReadiness Service and Black Screen

We have solved the problem.
It was a latency caused by the loading of the windows app base at each user connection.
Indeed, this database is loaded and read for each connection and its size increases which slows down the connection process (event viewer\Applications and Services Logs\Microsoft\Windows\AppReadiness\Admin)
You must therefore stop the service, delete the files located under %ProgramData%\Microsoft\Windows\AppRepository\StateRepository* and restart the service.
Be careful because the modification of the key of register will handicap the operation of the service and can in the long run make disfonctionnement largely Windows, the office suite, the maj Windows and cause problems to the user profiles.
https://msendpointmgr.com/2021/08/30/fslogix-slow-sign-in-fix-redux/

LeonT585