Re-enable Basic Authentication in Office 365 - Exchange Online
How to use the Microsoft self-service diagnostic tool to re-enable Basic Authentication in Exchange Online
Disabling basic authentication in Exchange Online
Microsoft have been advising customers for some time that they will be disabling basic authentication in Exchange Online to improve security.
What you need to know about basic authentication deprecation
- Microsoft will start to disable basic authentication in randomly selected Office 365 tenants from 1st Oct 2022
- Basic authentication access will be disabled for these protocols:
MAPI, RPC, Offline Address Book (OAB), Exchange Web Services (EWS), POP, IMAP, Exchange ActiveSync (EAS), and Remote PowerShell - SMTP AUTH will not be disabled
How can I re-enable basic authentication in Office 365?
If you have not yet migrated to using Microsoft Graph. Microsoft have a self-service diagnostic tool that you can use to re-enable basic auth for the protocols that are still using it.
Using the self-service diagnostic tool to re-enable basic auth
Sign into the Office 365 admin portal
https://admin.microsoft.com
Help & support
Enter "Diag: Enable Basic Auth in EXO" and click Run Tests
Select the protocol you want to re-enable
e.g. Exchange Web Services (EWS)
Tick to acknowledge the settings change and click update
Reference:
by Author
Basic Authentication Deprecation in Exchange Online – September 2022 Update

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