Title: Users may be unable to join Microsoft Teams meetings and see sign-in errors User impact: Users may be unable to join Microsoft Teams meetings and see sign-in errors. More info: Affected users see a sign-in prompt when attempting to join a meeting but clicking "sign-in" on the prompt has no effect. Users can sign-out and sign back in as a temporary mitigation. Current status: We've halted the code change causing this problem to ensure that no additional users encounter Microsoft Teams meeting join and sign-in errors. We're deploying a code fix to remediate the issue for users who received the code change prior to us halting it. Users will experience progressive relief from the issue as this deployment reaches them and we expect the code fix to propagate fully around the time of our next update. Scope of impact: Some users may be unable to join Microsoft Teams meetings and see sign-in errors. This information may be updated as our investigation continues. Root cause: A recent change to the authentication flow utilized in the event contained a regression, resulting in this impact. Next update by: Thursday, October 15, 2026, at 11:30 PM UTC
We have validated the fix and are working towards production rollout. The earlier mitigation, which disabled a related feature, remains in effect to limit customer impact. There's no estimated resolution time at this point. We'll share another update when more information is available.
We are continuing to monitor for any further issues.
