Microsoft is working to restore its Microsoft 365 services after a widespread global outage disrupted access to Outlook, Teams, Copilot and several other workplace applications on November 12 and 13, 2026. The disruption affected users across multiple countries, leaving many unable to access emails, calendars and other essential business tools.
The outage began on Thursday and continued into Friday morning in India. Downdetector recorded nearly 140,000 reports of Outlook-related problems at the peak of the disruption.
Exchange Online Failure Behind the Outage
The primary issue was linked to Exchange Online, Microsoft’s cloud-based email and calendar platform that powers Outlook for business and enterprise customers.
Microsoft reported that affected servers had become unavailable unexpectedly, creating additional pressure on the remaining infrastructure. The company also found that a process responsible for establishing secure connections on affected servers was becoming overwhelmed, preventing them from processing requests.
The disruption was not limited to Outlook. Several Microsoft 365 services that depend on Exchange Online experienced problems, including Teams calendar functions, SharePoint features, Microsoft 365 Copilot and other enterprise applications.
Microsoft said core Teams messaging and online meetings remained largely functional, although some features such as meeting scheduling and chat creation were affected.
ChatGPT and Claude Connectors Also Impacted
The outage extended beyond Microsoft’s own applications. OpenAI and Anthropic also reported problems with Microsoft 365 connectors used by their AI services.
These connectors allow AI assistants such as ChatGPT and Claude to access workplace information, including emails, calendars and files, when users have connected their Microsoft accounts.
As a result, some users experienced difficulties accessing work-related information through these integrations.
Microsoft’s Recovery Efforts Face Challenges
Microsoft initially attempted to restore affected servers by restarting infrastructure and redirecting traffic. However, some servers became unresponsive again after traffic returned.
The company subsequently tested alternative health-check methods, configuration changes and traffic-management measures to improve server stability.
In a later update, Microsoft acknowledged that some changes were not working as expected and said it was exploring alternative approaches to increase capacity and restore service.
The company had not provided a confirmed timeline for complete recovery as of November 13.
Microsoft also indicated that it did not believe the incident was caused by a cyberattack. The precise root cause remained under investigation.
What Users Can Do to Fix Outlook and Other Apps
Since the disruption is linked to Microsoft’s infrastructure, users cannot independently fix the underlying problem. However, they can try a few steps once services begin recovering:
- Check the Microsoft 365 Service Health dashboard for updates on affected services.
- Refresh Outlook or sign out and sign back into the application.
- Restart the Outlook desktop application or browser.
- Check internet connectivity and try accessing Outlook through another device.
- Avoid repeatedly reinstalling applications or changing account settings while Microsoft is addressing the outage.
- If emails remain delayed, check the mailbox again after Microsoft confirms service restoration.
Users should also avoid assuming that an email has been delivered successfully simply because it appears in the Outbox.
Businesses Face Disruption to Daily Operations
The incident highlights how businesses increasingly depend on centralised cloud platforms for email, communication, file sharing and productivity.
Government departments, educational institutions and businesses were among those reporting disruptions. The outage also affected certain services in Australia and other international markets.
For organisations relying heavily on Microsoft 365, even a disruption concentrated around Exchange Online can affect several interconnected business applications.
Summary
Microsoft’s global outage on November 12–13 disrupted Outlook, Teams, Copilot and other Microsoft 365 services because of problems affecting Exchange Online and its supporting infrastructure. Recovery efforts continued as some servers remained unstable after restarting. Microsoft said it did not believe the incident was a cyberattack but had not confirmed a full recovery timeline or definitive root cause.
