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Microsoft Defender for Office 365: Admins can block external users in Microsoft Teams from Defender Portal

Roadmap ID
542189
View in M365 Roadmap
Products
Microsoft Defender for Office 365Microsoft Teams
Published
December 12, 2025
Status
Rolling out
Cloud Instance
Worldwide (Standard Multi-Tenant)
Release Phase
General Availability
Platform
Web
Expected Release
February 2026

Description

Security admins with Defender for Office 365 Plan 1 and above can block external users from sending messages, calls, meetings invitation over Microsoft Teams via the Tenant Allow Block List in Microsoft Defender portal. Updated January 28, 2026: We are pausing rollout at this time as we address an ongoing issue. We apologize for any inconvenience.

Change History

Show
February 18, 2026 at 2:00 AM Updated
Status
Previous
In development
New
Rolling out
Modified Date
Previous
2026-01-29T00:15:19.000Z
New
2026-02-18T00:00:38.000Z
January 29, 2026 at 2:00 AM Updated
Description
Previous
Security admins with Defender for Office 365 Plan 1 and above can block external users from sending messages, calls, meetings invitation over Microsoft Teams via the Tenant Allow Block List in Microsoft Defender portal
New
Security admins with Defender for Office 365 Plan 1 and above can block external users from sending messages, calls, meetings invitation over Microsoft Teams via the Tenant Allow Block List in Microsoft Defender portal. Updated January 28, 2026: We are pausing rollout at this time as we address an ongoing issue. We apologize for any inconvenience.
Status
Previous
Rolling out
New
In development
Release Date
Previous
January CY2026
New
February CY2026
Modified Date
Previous
2026-01-06T23:45:19.000Z
New
2026-01-29T00:15:19.000Z
January 7, 2026 at 2:00 AM Updated
Status
Previous
In development
New
Rolling out
Modified Date
Previous
2025-12-12T23:00:26.000Z
New
2026-01-06T23:45:19.000Z

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