Service Announcement - 21 April 2026 Microsoft Office: April Update may unintentionally Switch to New Outlook

The April 2026 updates for Microsoft Office may, under certain circumstances, result in an unintended switch from Outlook Classic (Legacy) to New Outlook.
New Outlook is not compatible with Exchange on-premises.

To undo this unintended change, simply click “Legacy Outlook” under “Outlook” in the menu bar.