Microsoft announced that Teams will automatically enable messaging safety features by default to strengthen defenses against content tagged as malicious.

The change will roll out starting January 12, 2026, to tenants still using the default configuration and who haven't previously modified messaging safety settings.

"We're improving messaging security in Microsoft Teams by enabling key safety protections by default," Microsoft toldadministrators in a Microsoft 365 message center update. "This update helps safeguard users from malicious content and provides options to report incorrect detections."

Microsoft said the update will activate three key security features: weaponizable file type protection, malicious URL detection, and a system for reporting false positives. As previously noted, organizations that previously customized these settings will see no changes.

After the messaging protections are enabled, users may notice warning labels on messages containing suspicious URLs and the ability to flag incorrect security detections, while messages containing potentially dangerous file types will be blocked entirely.

Administrators who prefer to maintain current settings should review their Teams admin center configurations before the January deadline. Organizations that want to use different security parameters must adjust settings and save changes before January 12 to prevent automatic activation.

The company advised IT admins to update internal documentation and communicate these changes to helpdesk staff. Teams administrators can review current configurations by navigating to Messaging > Messaging settings > Messaging safety in the Teams admin center.

These changes are part of Microsoft's response to increased scrutiny over cybersecurity risks, which also includes a feature that warns admins about suspicious traffic from external domains, as cybercriminals target Teams customers in phishing attacks and malware campaigns.

In recent weeks, Microsoft has also rolled out a new Teams feature that automatically blocks screen-capture attempts during meetings and announced that it's working on a new call handler to speed up the Teams desktop client, improving launch times and performance on Windows 11 systems.

During last year's Enterprise Connect conference, Microsoft revealed that over 320 million people use its Teams workplace collaboration platform each month.