Admins may be unable to enforce Data Loss Prevention (DLP) policies in Microsoft Teams

Title: Admins may be unable to enforce Data Loss Prevention (DLP) policies in Microsoft Teams User impact: Admins may have been unable to enforce DLP policies in Microsoft Teams. More info: DLP policies configured in Microsoft Purview successfully detected policy matches, but the expected enforcement actions weren't being applied within Microsoft Teams. As a result, messages that should have been blocked may have continued to be delivered. This applied to all Microsoft Teams channels. Final status: We've validated through our testing that an authentication configuration change made to the service infrastructure affected the enforcement of DLP policies, which led to impact. We've successfully deployed our fix to roll back this configuration change in all environments and confirmed that impact has been resolved. Scope of impact: Any admin may have been impacted and may have been unable to enforce DLP policies in Microsoft Teams. Start time: Monday, June 22, 2026, at 7:00 AM UTC End time: Thursday, July 23, 2026, at 4:20 AM UTC Root cause: An authentication configuration change made to the service infrastructure affected the enforcement of DLP policies, which led to impact. Next steps: - We're reviewing our feature update testing and validation methods to better identify the potential for impact to DLP policies prior to deployment to prevent similar impact in the future, and to improve our pre-deployment update testing processes. This is the final update for the event.

Title: Admins may be unable to enforce Data Loss Prevention (DLP) policies in Microsoft Teams User impact: Admins may be unable to enforce DLP policies in Microsoft Teams. More info: DLP policies configured in Microsoft Purview successfully detect policy matches, but the expected enforcement actions aren't being applied within Microsoft Teams. As a result, messages that should be blocked may continue to be delivered. This applies to all Microsoft Teams channels. Current status: We're continuing to validate our potential fix and so far, we're seeing positive results. We're continuing to test this fix to ensure it fully resolves the issue before we begin expanding the fix deployment to all impacted environments. Scope of impact: Any admin may be impacted and may be unable to enforce DLP policies in Microsoft Teams. This section may be updated as our investigation continues. Next update by: Thursday, July 23, 2026, at 4:30 AM UTC

Title: Admins may be unable to enforce Data Loss Prevention (DLP) policies in Microsoft Teams User impact: Admins may be unable to enforce DLP policies in Microsoft Teams. More info: DLP policies configured in Microsoft Purview successfully detect policy matches, but the expected enforcement actions aren't being applied within Microsoft Teams. As a result, messages that should be blocked may continue to be delivered. This applies to all Microsoft Teams channels. Current status: We've identified an issue with DLP policies in Microsoft Teams not being enforced correctly. We’ve investigated the impacted service environment and identified a token error in the service infrastructure logs, and we believe we've correlated the error with a recent authentication configuration change that may be causing impact. We've developed a potential fix, and we’re validating this fix in a small testing environment to confirm this fix addresses the impact fully. Scope of impact: Any admin may be impacted and may be unable to enforce DLP policies in Microsoft Teams. This section may be updated as our investigation continues. Next update by: Thursday, July 23, 2026, at 2:30 AM UTC