A major Microsoft 365 outage left thousands of users unable to access essential workplace applications on November 12 and 13, 2026, with disruptions lasting more than nine hours.
The Guardian reported that nearly 130,000 problems were recorded across 74 countries, affecting Outlook, Microsoft Teams, Word, Excel, PowerPoint, OneDrive, SharePoint and Copilot.
Microsoft confirmed that it was investigating the disruption and said there was no indication of a cyberattack.
The company identified possible server configuration issues and increased traffic loads as contributing factors. Several recovery attempts were unsuccessful, with some servers becoming unavailable again after traffic returned.
Outlook’s Exchange services experienced significant problems, while Teams chats and meetings were less severely affected. Microsoft also restored some Teams functionality in North America, although connectivity issues continued for certain users.
The disruption extended beyond Microsoft’s own applications, affecting integrations connected to OpenAI and Anthropic services.
Microsoft continued working to restore affected systems, redirect traffic, and stabilize its infrastructure as users experienced interruptions to email, collaboration tools, and cloud-based productivity services.