On November 12, 2026, multiple Microsoft 365 services experienced disruptions, including Outlook, Exchange Online, Teams, OneDrive, SharePoint and Microsoft 365 Copilot. Microsoft said users in any region could be affected; one report said the applications were offline for more than six hours for some users worldwide. Downdetector figures cited by TechNews Taiwan and IT之家 ranged from more than 38,000 Microsoft 365 reports and more than 97,000 Outlook reports at a stated time to nearly 50,000 Microsoft 365 reports and nearly 130,000 Outlook reports at different points. These reports do not represent affected-user counts. Microsoft paused deployments and configuration changes, redistributed traffic and restarted servers. Its investigation found that many servers had unexpectedly become unavailable, placing greater load on the remainder, but Microsoft had not confirmed the underlying root cause. OpenAI and Anthropic separately reported problems affecting their Microsoft connectors; the reports did not establish whether those issues were part of the same failure chain.