Microsoft 365 outage still disrupting Outlook and email worldwide

On 13 November 2026, Microsoft's public service health page still listed a service degradation across Microsoft 365, after problems that began the previous afternoon. Features that interact with Exchange Online and email are affected; parts of those services that do not depend on Exchange Online remain functional. Microsoft 365 Status first reported Exchange Online mailbox access problems at 17:54 GMT on 12 November, initially in the Americas, and at 18:07 GMT said connectivity may be affected for users in any region. It is tracking the work as Exchange incident EX1550543 and Microsoft 365 suite advisory MO1550821. Recovery is still under way. In its 09:14 GMT update on 13 November, Microsoft said it was seeing early signs of stabilisation, but that service capacity had not returned to normal and health remained variable as traffic was carefully reintroduced. It said it was not aware of any malicious activity causing the incident, and that it will publish a post-incident report with the root cause after recovery is complete.

What happened

Microsoft 365 Status said at 18:35 GMT on 12 November that a portion of its infrastructure was under elevated load across multiple regions, which was likely contributing to the connectivity errors. At 19:31 GMT it said the elevated load was not driven by an increase in traffic, but by a number of servers being unexpectedly unavailable, which was straining the remaining infrastructure.

Through the evening, Microsoft said servers were failing automated health checks and dropping out of service, that a core process on the affected servers was becoming overwhelmed, and that servers returned to service could become unresponsive again once they received traffic. It paused deployments, redistributed traffic, restarted servers, tested alternative health checks, and later applied traffic optimisation and temporary limits on which types of traffic could reach affected infrastructure in some locations.

Fixes did not hold at first. At 03:13 GMT on 13 November, Microsoft 365 Status said changes applied to improve serviceability were "not taking as expected". Later updates described partial recovery in some regions, then positive results from traffic optimisation, then early stabilisation and capacity improvements. Microsoft has not yet published a root cause, and says a full post-incident report will follow once recovery is complete.

Who is affected

The impact is worldwide. Microsoft's 13 November status update lists these effects on business and enterprise Microsoft 365:

• Exchange Online and Outlook: users may be unable to access their mailbox using Outlook on the web, Outlook desktop (MAPI), Exchange ActiveSync or REST-based connections, and email delivery may be delayed.
• Microsoft 365 admin centre: admins may be unable to load some pages.
• Microsoft 365 apps and the Apps admin centre: users may be unable to view recently used files; Cloud Update, Cloud Policy and Inventory are affected.
• Microsoft 365 Education: Assignments, Reading Progress and Speaker Progress may be impacted.
• Microsoft Copilot 365: users may be unable to load Copilot Chat or get responses in the web and desktop apps, and Copilot may be unable to access work data such as email, calendar and files.
• Microsoft Defender for Office 365 and Defender XDR: Safe Links, Safe Attachments, quarantine, Threat Explorer and related protection and portal features may fail; users may be unable to load Defender portal pages.
• Microsoft Purview: several services, including data loss prevention, information protection, role-based access control and eDiscovery, may be impacted, and users may be unable to open the Purview portal or protected content.
• Microsoft Graph, Intune, Planner, Power Apps, Fabric, Power BI, To Do, Universal Print and Windows 365: Graph requests for Exchange data may time out; Intune enrolment, check-in and compliance may have been intermittently impacted; Planner task operations may fail; Power Apps and Field Service mobile sign-in may fail; Fabric and Power BI exports that use sensitivity labels may fail; To Do may not load; Universal Print jobs may fail; and Windows 365 Cloud PCs that use Microsoft Purview Customer Key may be unreachable.
• SharePoint Online: accessing files stored in SharePoint remains functional, but some users may have problems sharing files with people outside their organisation, and features that depend on Exchange Online may be affected.
• Microsoft Teams: joining calls, meetings, group chats and channel messages is largely unaffected. Calendar scheduling, invitations, meeting edits, Live or Virtual events, some Copilot responses, app chats, contact sync, and creating or deleting private or shared channels may fail.

Microsoft's consumer status still lists a Microsoft 365 (Consumer) service degradation, last updated at 06:24 GMT on 13 November, saying users may be unable to access or use Outlook.com, OneDrive, OneNote, Microsoft To Do, Teams and Microsoft 365 for the web, and may also see issues in other Microsoft 365 services. Microsoft's Azure status reports no Azure issues at this time.

The remedy

There is no customer patch, and the outage is not fully resolved. Microsoft says recovery is continuing across the affected infrastructure, with engineering teams cycling systems through traffic drain, restart, remediation and a staged return to service. Network and traffic-management work is still in progress. To help protect delayed mail, Microsoft has extended the email timeout window to 48 hours.

Microsoft lists a few limited workarounds while recovery continues:

• Power Apps and Field Service users who cannot sign in on mobile can use the web apps. People who are already signed in should avoid signing out, clearing app data or reinstalling while the issue is ongoing.
• Fabric users who cannot export or update items that have a sensitivity label can remove the label to complete the operation, if their organisation's data protection policies allow it.

Administrators should follow EX1550543 and MO1550821 in the Microsoft 365 admin centre, or use the public service health page if the admin centre will not load. Microsoft says it will treat the incident with urgency until it is fully mitigated, and will share a post-incident report after recovery is complete.

Sources

• Microsoft service health status
• Microsoft consumer service health status
• Microsoft 365 Status, 13 November 09:24 GMT