A Microsoft 365 outage that began shortly before 1 PM ET on Thursday, November 12, 2026, has cut many businesses off from Outlook email, with knock-on problems in Teams, Copilot and other Microsoft 365 services. Microsoft acknowledged the incident on its Microsoft 365 Status account and said the problems were mainly with Exchange Online. On Friday morning, Business Standard reported Microsoft saying recovery was limited and the outage could persist for some time.

What’s new

According to Microsoft’s updates, as reported by The Verge and Business Standard, a process that sets up secure connections on the affected servers became overloaded, and some servers then failed automated health checks. Microsoft said it is restarting infrastructure, testing a configuration change on a subset of servers, reversing a recent network change and limiting traffic in some locations while it recovers. Charles Lamanna, an executive vice president at Microsoft, said the outage was not caused by a cybersecurity breach.

  • Outlook on web, desktop and mobile: mailbox access errors and delayed email delivery
  • Copilot: chat not loading and trouble reaching work data
  • Teams: calendars and meeting scheduling affected, while core chat and meetings mostly worked
  • Admin center pages, Planner, To Do, SharePoint Online and several other services in part

Who it affects

Any business that runs its email on Microsoft 365, in any region. Small teams feel it most because email is often the only channel for quotes, invoices and customer questions. This is a server-side problem at Microsoft, so nothing on your own laptops or phones is broken.

Our take

Don’t reset passwords, reinstall Outlook or change mail settings; none of that will help, and it creates work later. Give customers another way to reach you today, such as a phone or WhatsApp line in your website banner or social pages. Once service returns, check that time-sensitive messages arrived and resend anything important you sent during the outage. Be wary of emails or calls offering to fix the problem, since outages are a common hook for phishing. You can follow live updates on Microsoft’s service status page and in Service health in the Microsoft 365 admin center.

For a recent Microsoft security issue that does need action, see our note on the November Outlook zero-day. If you’d like a backup plan for the next outage, our IT consulting team can help you set one up.