Global Microsoft service outage affects users in more than 70 countries

A global outage of Microsoft services occurred on November 12 and 13, 2026, impacting millions of users across more than 70 countries. The disruption affected several major products, including Outlook, Teams, and Copilot. The outage lasted nearly 18 hours for millions of users, causing significant interference in various sectors including banking, airlines, healthcare, and education.

Scope of the disruption

The technical failure caused widespread issues for a variety of essential services. The United States federal government and court systems reported issues related to the outage. In the United Kingdom, the National Health Service reported that the outage caused unavoidable interference for staff, although medical appointments continued as scheduled. Some schools reported that the disruption required parents to communicate via telephone to coordinate with educational institutions.

The impact extended to the artificial intelligence sector, as the outage affected connection components used by OpenAI and Anthropic. Data from Downdetector showed significant user frustration, with the platform recording hundreds of thousands of complaints. At one point, Outlook alone saw a peak of 138,058 problem reports. While Microsoft reported service improvements in North America, Europe, and the Asia-Pacific region on November 13, 2026, officials noted that some of the 20 affected products and services may continue to encounter errors.

Cause and official response

Microsoft issued an apology for the disruption on November 13, 2026, stating they are deeply sorry for the disruption. Regarding the technical origin of the failure, Microsoft identified the cause as an overwhelmed core process on affected servers. Some reports suggested the fault was caused by a previous network capacity upgrade, though Microsoft clarified the issue was not caused by cyberattacks or AI agent activity.

Historical context of service outages

This event follows previous large-scale digital disruptions that have impacted global infrastructure. In 2024, a faulty software update from the cybersecurity firm CrowdStrike caused global system crashes and flight groundings. Additionally, a 15-hour disruption at Amazon Web Services in 2025 impacted hundreds of websites. These incidents highlight the potential for widespread systemic failure when core digital services experience technical difficulties.

Glossary

• National Health Service — The National Health Service is a system where specialist doctors or diagnostic tests are provided by public hospitals or by private ones with contracts. It provides services that may require a copay if prescribed by a family doctor and are free for the poor.
• OpenAI — OpenAI is a company in the artificial intelligence sector. It uses connection components that can be affected by service outages.
• Anthropic — Anthropic is a company in the artificial intelligence sector. It uses connection components that can be affected by service outages.