In August, Microsoft announced that beginning October 1, 2022, Microsoft will begin to permanently disable Basic Authentication in all tenants, regardless of usage, except for SMTP Auth. To learn more about the deprecation of Basic Authentication, read the announcement at Exchange Team Blog > Basic Authentication and Exchange Online – September 2021 Update.
On September 1, Microsoft announced an update for the plan to offer customers who are unaware of or are not ready for this change.
When Microsoft 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 the end of December 2022. During the first week of the 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