We wanted to give you a quick pointer to a blog post that was posted on the Microsoft 365 Blog:
New minimum Outlook for Windows version requirements for Microsoft 365
After November 1, 2021, only Outlook 2013 Service Pack 1 (with latest fixes) and later will be able to connect to Microsoft 365 services.
Please check the Microsoft 365 blog for more information about this change!
Update 10/12/2021: For admins who would like to know what versions of Outlook are active in their tenant, the Email apps usage report provides a full list of all users and Outlook versions in use within a tenant. For more information, see Microsoft 365 Reports in the admin center - Email apps usage.
Nino Bilic
