In August, Microsoft announced that, beginning October 1, 2022, they will begin to permanently disable Basic Authentication in all tenants, regardless of usage, except for SMTP Auth.
On September 1, Microsoft announced an update to our plan to offer customers who are unaware of or are not ready for this change.
When we turn off Basic Authentication after October 1, all customers will be able to use the self-service diagnostic to re-enable Basic Authentication for any protocols they need, once per protocol. After this diagnostic is run, Basic Authentication will be re-enabled for those protocols. Selected protocols will stay enabled for Basic Authentication use until end of December 2022. During the first week of calendar year 2023, those protocols will be disabled for Basic Authentication use permanently, and there will be no possibility of using Basic Authentication after that.
- Microsoft Docs article: Deprecation of Basic Authentication in Exchange Online
- Latest Tech Community blog post: Basic Authentication Deprecation in Exchange Online – September 2022 Update
- Tech Community blog post: Microsoft and Apple Working Together to Improve Exchange Online Security
- CISA guidance: Switch to Modern Authentication in Exchange Online Before Basic Authentication Deprecation