MDK 401 response

[Facundo_Quevedo]

Hi expert i m facing this problem, today our mobile app thorw the next message.
Yesterday it was working and we didnt make any changes.

[bill_froelich]

The error message indicates a problem for the use to retrieve the metadata for the backend service.  Could the user be locked out of the backend for some reason or is the new metadata using a different / new service that the user might not have access to?