Microsoft 365 Outage: Outlook, Teams Down Worldwide

A major Microsoft 365 outage has disrupted email, collaboration and productivity tools for millions of users worldwide, more than 12 hours after the incident began on 12 November 2026. The disruption has hit Microsoft Outlook, Microsoft Teams, SharePoint Online, OneDrive and Copilot, leaving businesses and individuals unable to send mail, join meetings or access documents.

What Caused the Microsoft 365 Outage?

Microsoft said the global service disruption was caused by “elevated load” on its infrastructure after a number of servers unexpectedly became unavailable. According to the company, those servers failed automated health checks, forcing the remaining infrastructure to absorb the extra traffic. The Microsoft 365 service status page tracked the incident under ID MO1550821.

“A number of servers are unexpectedly unavailable, which puts the remaining infrastructure under pressure,” Microsoft said on X. The company has ruled out a cyberattack and stressed that there is no indication of malicious activity.

Timeline of the Disruption

• 12 November, 17:15 CET: The outage became widely noticeable as Outlook and Exchange Online mailbox access failed in multiple regions.
• 12 November, 1:26 PM ET: Microsoft’s incident log shows Exchange Online problems in the Americas began earlier in the day.
• 13 November, 03:15 CET: Microsoft said attempts to restart affected systems had not yet produced the desired result.
• 13 November morning: Recovery remained limited and gradual, with no confirmed full restoration.

Which Services Are Affected?

The outage is not limited to a single app. Users around the world have reported problems with:

• Outlook and Exchange Online (email)
• Microsoft Teams (chat and online meetings)
• SharePoint Online and OneDrive
• Word, Excel and PowerPoint via Microsoft 365
• Microsoft 365 Copilot and AI features

Downdetector recorded nearly 130,000 reports for Outlook at the peak, with additional spikes for Microsoft 365, Azure and OneDrive. The disruption has been felt in at least 74 countries, according to reports.

Microsoft’s Response and Recovery Efforts

Microsoft said it paused all deployments, shifted traffic away from the affected infrastructure and restarted servers. Some of those servers became unavailable again once load returned, which slowed recovery. The company’s corporate vice president Charles Lamanna apologised to customers.

“We regret that today’s outages have caused inconvenience for our customers, and we are working to resolve the issue,” Lamanna said.

Cybersecurity expert Mark Gregory described the incident as a cascading cloud infrastructure failure, noting that overloaded remaining servers made the problem worse. He urged organisations to test backup providers and avoid relying on a single vendor.

How to Check If Microsoft 365 Is Down

1. Visit the Microsoft 365 admin center or status page.
2. Check Downdetector or other outage trackers for live reports.
3. Look for updates from Microsoft on X (formerly Twitter).
4. Avoid making configuration changes while the incident is active.

Impact on Businesses and AI Providers

With more than 430 million Microsoft 365 subscribers worldwide, the disruption has had a wide ripple effect. OpenAI and Anthropic, which rely on Microsoft infrastructure, also reported problems with their Microsoft connectors. The incident highlights how deeply cloud service dependencies are embedded in modern work.

Businesses that depend on Outlook for email and Teams for meetings faced lost productivity, delayed communications and interrupted workflows. Some organisations switched to alternative tools while waiting for restoration. The outage follows an earlier Azure disruption in October 2026, adding to concerns about resilience across major cloud platforms.

FAQ

Is the Microsoft 365 outage still ongoing?

As of 13 November 2026, Microsoft had not confirmed full restoration. Recovery was limited and gradual, and the company said the disruption could continue for some time.

Was the Microsoft outage caused by a cyberattack?

No. Microsoft has ruled out a cyberattack and said there is no indication of malicious activity. The cause appears to be infrastructure overload after servers failed health checks.

Which countries are affected by the Microsoft outage?

The disruption has been reported in at least 74 countries worldwide, affecting users of Outlook, Teams, SharePoint, OneDrive and other Microsoft 365 services.

How many Microsoft 365 users are affected?

Microsoft 365 has more than 430 million subscribers globally. While not all users were impacted, millions experienced service problems during the outage.

What should I do if my Outlook or Teams is down?

Monitor the Microsoft 365 admin center or status page for updates. Avoid repeated restarts, and consider using alternative communication channels until services are restored.