Koen Verbeeck runs into an odd issue:
In the PowerShell function, this application setting is retrieved as an environment variable so it can authenticate with the Graph API using the app registation. So far so good, except that the secret of this app registration expires after 1 year (some time ago you could configure an expiration date for in the future, but it seems this isn’t possible anymore). The Azure Function started crashing with a 401 (Unauthorized) error.
Read on to see what Koen tried, what eventually fixed it, and a pair of updates to the post.