Starting mid-September 2026, Viva Engage will stop sending email notifications to users without valid mailboxes, reducing email system load and improving delivery. Users with supported mailboxes will be unaffected. Notifications via Teams remain unchanged. No action is required, but admins should review mailbox configurations and update support documentation.
Applies to: Microsoft Viva
Source: mc.merill.net — data via Merill Fernando's open archive (MIT).