Microsoft announced earlier this month that it's planning to deprecate the Exchange Web Services API for Office 365 users.

SEE: Windows 10: A cheat sheet (TechRepublic) However, that only shows one set of applications, and others might be using Basic Authentication to sign in across all the other Office 365 services.

How to implement basic password authentication for a minimal API in ASP.NET Core using a custom authentication handler that validates the user’s credentials against a database.