Rolling out
Microsoft Defender for Office 365
Microsoft Teams
Worldwide (Standard Multi-Tenant)
General Availability
Web
January 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
Change History
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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