Thread experienced a major incident on January 22, 2026 affecting Thread Inbox, Messenger, & Admin, lasting 18h 33m. The incident has been resolved; the full update timeline is below.
Affected components
Thread Inbox, Messenger, & Admin
Update timeline
- investigating Jan 22, 2026, 08:46 PM UTC
We are currently experiencing an issue where emails sent from our environment to recipients hosted on Microsoft 365 (including Outlook.com and Exchange Online) are being delayed or not received. If you use SSO for sign in you should be unaffected.
- investigating Jan 22, 2026, 08:47 PM UTC
We are continuing to investigate this issue.
- investigating Jan 22, 2026, 08:59 PM UTC
We have verified email addresses not hosted by Microsoft are unaffected and are able to sign in as usual
- investigating Jan 22, 2026, 09:10 PM UTC
You can monitor the outage here https://status.cloud.microsoft/m365/referrer=serviceStatusRedirect.
- resolved Jan 23, 2026, 03:19 PM UTC
This incident has been resolved.