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.

Phasing out Basic Authentication is, to be honest, a sensible decision. One of the older web authentication protocols, it uses cleartext usernames and passwords to control access to services.

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

Microsoft has an update for Office 365/Microsoft 365 Exchange Online Basic Auth retirement in the case of SMTP.