Microsoft global Outlook outage disrupts hundreds of millions of users for 19 hours

Nov 13, 2026

A global Microsoft 365 cloud outage starting November 12, 2026, disrupted email, Teams, and Copilot services for over 19 hours, affecting up to 500 million users across 70 countries. Triggered by server stress following a network change, the incident caused significant delays across UK health services, North American municipal offices, courts, and global financial markets. Organizations resorted to faxes, phone calls, and paper records, highlighting vulnerabilities in centralized cloud dependence and automated AI workflows.

Cause and technical response

▪Microsoft extended its email timeout window to 48 hours during the November 2026 outage to help protect delayed messages from being lost
▪Microsoft and cybersecurity experts confirmed that the global Microsoft 365 outage that began on Nov. 12, 2026 was not caused by a cybersecurity breach or malicious activity
▪Microsoft stated that the November 2026 global outage was caused by a technical issue following a recent network change on Nov. 12, 2026

Disruption to government and parliamentary operations

▪Municipal governments across North America, including the cities of Austin, Jacksonville, and Baltimore, experienced disruption to email and administrative services during the November 2026 Microsoft outage
▪UK Cyber Minister Baroness Lloyd of Effra held discussions with Microsoft UK chief executive Darren Hardman regarding the mitigation of the public sector impact of the outage
▪The Scottish government activated its resilience operations on November 13, 2026, to assess and manage the impact of the Microsoft cloud outage on public services

Impact on law enforcement and courts

▪Police forces across England and Wales, including the Metropolitan Police and Greater Manchester Police, advised the public to call 101 for non-emergency reports after their online contact forms were affected by the Nov. 12, 2026 Microsoft 365 outage
▪The Nov. 12, 2026 Microsoft outage disrupted court operations, causing delays to criminal trials at Manchester Minshull Street Crown Court and forcing New York City's Department of Investigations to suspend evictions
▪The Arapahoe County Sheriff's Office in Colorado instructed individuals posting bond for immediate inmate release to pay in person at the jail after online payment systems were disrupted

Disruption to business and financial operations

▪Financial institutions in Taiwan reverted to using paper fax machines and telephone calls to execute and confirm short-term bill transactions during the Nov. 12, 2026 Microsoft 365 email outage
▪European stock exchange operator Euronext instructed listed companies to communicate via telephone and verified caller identities to maintain operations during the Nov. 12, 2026 Microsoft cloud outage
▪Shipping operator Maersk warned customers during the November 13, 2026 Microsoft outage that emails were delayed and advised clients to call local offices to confirm urgent requests

Effects and mitigations for AI systems

▪During the Nov. 12, 2026 Microsoft 365 email outage, AI agents processing customer service inboxes risks treating a delayed email as a quiet inbox and later executing outdated requests out of order
▪During the global Microsoft 365 outage that began on Nov. 12, 2026, third-party AI connections including Anthropic's Claude and OpenAI's ChatGPT experienced widespread errors accessing Microsoft 365 mailboxes