Feb 13, 2024, users connecting to Exchange Online with the latest version of Outlook Desktop are being impacted, as reported today by Petri and Windows Report news sites. The issue has been occurring since early February and is under investigation by Microsoft.

The ActiveSync issues are specific to those with 365 Exchange Online, and those with Microsoft Exchange Servers are not affected.

If your users are being impacted, one temporary workaround for your 365 users is to revert to the prior version or semi-annual channel release of Outlook desktop.

Two articles discussing the issue:


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