What you need to know:
To ensure that Microsoft meets performance expectations, they are updating the supported versions of Outlook for Windows that can connect to Microsoft 365 services.
Starting November 1, 2021, the following versions of Outlook for Windows, as part of Office and Microsoft 365 Apps, will not be able to connect with Office 365 and Microsoft 365 services.
Office and Microsoft 365 Apps
Outlook for Windows Version
15.0.4970.9999 and older
16.0.4599.9999 and older
Microsoft 365 Apps for enterprise (formerly Office 365 ProPlus)
1705 and older
Microsoft 365 Apps for business (formerly Office 365 Business)
1705 and older
- Major: Retirement
- Timing: Beginning November 1, 2021 and will be complete by mid-May 2022
- Action: Ensure Outlook for Windows client is updated accordingly
How this will effect your organization:
Versions that are newer than the minimum version requirements listed above, but are not the currently supported version, may experience connectivity issues.
To see a list of the currently supported versions, visit Update history for Microsoft 365 Apps (listed by date) (for Microsoft 365 Apps) or Latest updates for versions of Office that use Windows Installer (MSI) (see “Latest Public Update” for Office 2013 and 2016).
Supported versions of Outlook for Windows in Office and Microsoft 365 will continue to connect to Microsoft 365 services as expected.
What you need to do to prepare:
We recommend that all users upgrade to the supported versions of Office and Microsoft 365 Apps.
If you have any questions, please reach out to an Alchemist.