According to Microsoft there's an outage with Exchange Online
Users may be unable to connect to their mailboxes in Exchange Online through multiple connection methods
Issue ID: EX1550543
Affected services: Exchange Online
Status: Service degradation
Issue type: Incident
Start time: Nov 12, 2026, 11:17 AM EST
User impact
Users may be unable to connect to their mailboxes in Exchange Online through multiple connection methods.
More info
Potentially impacted connection methods may include:
- Outlook on the web
- Messaging API (MAPI)
- Exchange ActiveSync (EAS)
- Representational State Transfer (REST) API
Scope of impact
This issue may affect users in North America, Latin America, Canada, Chile and Mexico.
Current status
Nov 12, 2026, 11:55 AM EST
We're reviewing service health telemetry information to identify and isolate any errors contributing to impact for further investigation.
Next update by:
Thursday, November 12, 2026 at 1:00 PM EST
More info: https://www.odu.edu/article/microsoft-exchange-outage
User impact: Users may be unable to connect to multiple Microsoft 365 services.
More info: More info: Potentially impacted services include:
- Exchange Online
- Microsoft Teams
- SharePoint Online
- Microsoft Copilot 365
- Microsoft Defender XDR
- Microsoft Planner
- Microsoft To Do
- Microsoft Purview: Multiple Purview services including Authorization, Auto Labelling, Data Loss Prevention (DLP), Communication Compliance, and Data Classification are impacted.
Current status: We've validated an alternative health check method on a subset of affected infrastructure, which allowed the servers in that subset to successfully return to service, and we're now applying this change more broadly. We're also preparing an automated recovery process to continually detect and restart unresponsive servers, to help keep them in service while this change progresses. Additionally, our review of recent changes has identified a small number of configuration updates that we're investigating as potential contributors to the issue.
Previous status: While validating the targeted change, we found that many of the affected servers have become unresponsive, which is preventing us from confirming whether the change is effective. We're restarting these servers so they can come back online with the change in place, and we're applying the same approach to additional affected portions of our infrastructure to validate the results more broadly.
Scope of impact: This issue may affect users attempting to access the affected Microsoft 365 services.
Next update by: Thursday, November 12, 2026, at 10:30 PM UTC
