138,000 Outage Reports, 74 Countries Hit: What Went Wrong With Microsoft's Services?

A major outage affecting Microsoft's email and workplace applications entered its second day on Friday, disrupting businesses and users across several countries, even as the technology giant reported progress in restoring its services following repeated recovery setbacks.

The disruption, which began on Thursday, November 12, affected Outlook, Microsoft Teams, Copilot and several other Microsoft 365 services, leaving users unable to access email accounts, load inboxes, send or receive messages and use certain workplace applications.

Outage-tracking platform Downdetector recorded more than 1.38 lakh reports of Outlook problems at the peak of the disruption. Complaints were reported across 74 countries, highlighting the widespread impact of the failure.

Microsoft initially traced the problem to unusually high loads on parts of its infrastructure. Its investigation found that several servers had unexpectedly become unavailable after failing automated health checks, placing additional pressure on the remaining systems.

The company's initial recovery attempts, including restarting affected servers and rerouting traffic, failed to deliver sustained results. Some servers became unresponsive again when user traffic returned.

However, Microsoft reported fresh progress on Friday after applying an authentication and routing configuration patch to part of its infrastructure. The company said it was seeing positive results in server stability and was gradually extending the fix to additional servers.

Availability and email delivery improved across North America, Europe and Asia-Pacific, although some users could still experience intermittent connectivity problems and delays as accumulated email backlogs were cleared.

The outage also affected services such as SharePoint, Planner, To Do, Microsoft Defender and Power BI, while some Teams features, including calendar access and meeting scheduling, experienced problems. OpenAI and Anthropic also reported difficulties connecting with Microsoft 365 tools.

In India, IndiGo and Air India reported email-related disruptions. However, both airlines confirmed that their flight operations remained unaffected. IndiGo said its alternative customer-support channels were operational, while Air India temporarily rerouted its email services to ensure passenger queries continued to reach the airline.

The disruption also affected government departments, businesses and public services in countries including the UK, Norway, Singapore, Japan and the Philippines. In Britain, a court trial in Manchester was halted, while some police forces faced difficulties receiving online crime reports.

Microsoft has said it has no indication that the outage was caused by malicious activity. The exact root cause remains under investigation, with the company expected to provide a detailed report after the incident is fully resolved.