To support a more consistent and secure email experience across Microsoft 365, we are transitioning to a unified domain for all product-generated emails. As part of this change, missed activity emails for Microsoft Teams will now be sent from teams.mail.microsoft instead of the previous teams.email.microsoft domain.
[When this will happen:]
- Public Preview: Rolling out early July 2025, expected to complete by early July 2025.
- Targeted Release: Rolling out early July 2025, expected to complete by early July 2025.
- General Availability: Rolling out mid-July 2025, expected to complete by late July 2025.
[How this will affect your organization:]
There is no impact to tenant configuration or admin settings. End users will simply see a new sender address for missed activity emails from Teams. No action is required from users or admins.
[What you can do to prepare:]
No preparation is needed. However, you may wish to inform your helpdesk or communications teams of the sender address change to avoid confusion or misidentification of legitimate messages.
Source: Microsoft