Mirror Review
November 13, 2026
The Microsoft global outage has disrupted access to Outlook, Microsoft Teams, and several Microsoft 365 services, affecting users and organizations across multiple countries. The disruption began on November 12, 2026, and continued into November 13 as Microsoft worked to restore its affected infrastructure.
The incident primarily involves Exchange Online, Microsoft’s cloud-based email service. Users have experienced problems accessing mailboxes, sending and receiving emails, and connecting to Microsoft applications that rely on Exchange Online.
Microsoft is tracking the disruption through two service incidents: EX1550543, covering Exchange Online mailbox access, and MO1550821, covering multiple Microsoft 365 services.
What Caused the Microsoft Global Outage?
Microsoft has identified server availability and secure-connection processing problems during its investigation into the Microsoft global outage. However, the company has not confirmed a definitive underlying root cause.
Microsoft stated in its service update:
“Our investigation has found that a process on the affected servers responsible for establishing secure connections becomes overwhelmed, causing the servers to stop processing requests.”
This placed additional pressure on the remaining infrastructure as Microsoft worked to restore server capacity.
Microsoft also began reversing a recent network configuration change that coincided with the start of the disruption. Microsoft is monitoring whether that change contributed to the recovery.
The Microsoft outage cause investigation also involves server restarts, configuration changes and traffic-management measures. Microsoft is testing these measures on affected infrastructure before expanding them more broadly.
Which Microsoft 365 Services Were Affected?
The Microsoft 365 outage has affected several applications, but not every feature within those services has stopped working. Microsoft clarified that functions relying on Exchange Online and email services are affected, while features that do not depend on those services may continue to work.
The reported impact includes:
- Microsoft Outlook and Exchange Online: Users may be unable to access mailboxes through Outlook on the web, desktop connections, Exchange ActiveSync, and REST-based connections. Email delivery may also be delayed.
- Microsoft Teams: Calendar access, meeting scheduling, and creating chats for organizations using Information Barriers may fail. Core messaging and online meetings remain largely functional.
- SharePoint Online: Features that depend on Exchange Online may experience problems, while direct access to files stored in SharePoint remains available.
- Microsoft Copilot: Users may be unable to load Copilot Chat or receive responses. Copilot may also have difficulty accessing workplace information, including emails, calendars, and files.
- Microsoft Defender: Safe Links may be unable to verify URLs, while some Defender XDR portal pages and solution tabs may not load.
- Microsoft Planner and Microsoft To Do: Users may experience reliability issues with plan and task operations.
- Microsoft Intune and Microsoft Purview: Microsoft included these services in its affected-service list, although its update did not specify the exact functionality affected.
These service-level distinctions are important when assessing the Microsoft Teams outage and other Microsoft 365 services affected by the incident. A problem with an email-dependent feature does not necessarily mean the entire application is unavailable.
How Did the Microsoft Outlook Outage Affect Users?
The Microsoft Outlook outage affected users attempting to access their work and personal mailboxes through supported Exchange Online connections. Some users could not load their inboxes, while others experienced difficulties sending or receiving messages.
The disruption extended beyond individual email accounts. Organizations relying on Microsoft 365 for communication, scheduling, and document workflows also experienced problems with connected applications.
Outage-monitoring platform Downdetector recorded nearly 130,000 reports of Outlook problems in the United States at the height of the disruption. These reports reflect user submissions and do not represent a confirmed count of affected customers.
Users in countries including India, Australia, and Japan also reported disruption. Government organizations and businesses were among those affected.
What Is Microsoft Doing to Restore Its Services?
Microsoft service restoration efforts focus on bringing affected servers back online, managing network traffic, and improving infrastructure stability.
Its recovery measures include:
- Restarting affected servers and gradually returning them to service.
- Redistributing network traffic across alternative infrastructure.
- Limiting certain types of traffic reaching affected servers.
- Testing configuration changes on selected servers.
- Reversing a recent network configuration change.
- Rebuilding some affected servers using an earlier software configuration.
Microsoft reported limited recovery in certain regions, but some servers became unresponsive again after receiving traffic. The company continued analyzing diagnostic data and testing recovery measures to prevent the problem from recurring.
As of the latest available incident update on November 13, both EX1550543 and
MO1550821 remained listed as service degradations. Microsoft had not confirmed that all affected services were fully restored.
Users and administrators can check the Microsoft 365 service status page for updates on the Microsoft 365 status and individual service incidents.
What Users Should Know About the Microsoft Global Outage
The Microsoft global outage has affected email access and several connected Microsoft 365 features, with disruption varying by application and function. Outlook and Exchange Online remain central to the incident, while other services have experienced problems where their features depend on Microsoft’s email infrastructure.
Microsoft continues to investigate the server issues and apply recovery measures. Until the company confirms full restoration, users may continue to experience intermittent access problems across affected services.
