A more than 12-hour outage of Microsoft Outlook and Teams disrupted communications for businesses and governments worldwide. Microsoft blamed server issues and said it is not aware of any malicious activity.

 

What happened

Microsoft said server issues caused the outage, which also hit its Copilot AI assistant. The company said a broader roll-out of software fixes was starting to stabilize the system. The outage blocked users from sending emails, managing calendars, and hosting virtual meetings.

It hit government agencies from Australia to Japan and the United States. Trading firms faced delays, some companies could not publish earnings, and airlines warned customers about communication lags. Microsoft said the outage affected features tied to Exchange Online, its cloud-based email and scheduling hub, while applications unconnected to it kept working. Exchange Online is Microsoft’s cloud-based email and scheduling hub. Microsoft said the outage hit the features that depend on it, while applications unconnected to it kept working.

 

What was said

Microsoft’s Service Health Status page reported, “We remain focused on addressing residual impact and ensuring reliable service restoration. At this time, we have no evidence of malicious activity associated with this incident.” across the affected apps and services. Microsoft said users may still face “intermittent issues” as recovery actions continue, with progress in Europe and improving access in North America. Microsoft later reported “positive results for server stability” after applying a patch and said it would expand the fix to other services once it had monitored progress. Microsoft has not confirmed full restoration.

 

The backstory

This is the second Microsoft disruption this year. The company also had a Microsoft 365 outage in January 2026 and another in October 2025. In October, Microsoft reported an outage of its Azure cloud platform that hit its productivity software and industries worldwide.

 

Why it matters

The outage shows how much damage one provider’s failure can do. A single Exchange Online disruption halted a bond repurchase in Europe, pushed Taiwanese financial firms to confirm trades by fax, and delayed earnings announcements at Workhorse Group and Richemont. It also limited the Metropolitan Police’s online crime reporting and forced NHS services onto paper records.

Microsoft has now logged several outages in just over a year, which turns a one-off failure into a pattern that customers will notice. Analysts note that steep switching costs may keep customers from leaving. Even so, the incident adds to growing questions about global reliance on a handful of Big Tech companies for essential software and cloud infrastructure.

 

The bottom line

A single server issue at one provider disrupted governments, hospitals, airlines, and financial markets at once. Organizations that depend on cloud-hosted email and collaboration tools should plan for how they will communicate when those tools go down.

Related: HIPAA Compliant Email: The Definitive Guide

 

FAQs

What is the difference between cloud-hosted and self-hosted email?

Cloud-hosted email runs on the provider’s servers and is managed by the provider, while self-hosted email runs on servers the organization owns and maintains itself.

 

Why can one outage affect so many organizations at once?

Many organizations rely on the same providers for core tools, so a single failure can spread across industries and countries simultaneously.

 

What is a business continuity plan?

A business continuity plan is a documented strategy that explains how an organization will keep operating when key systems fail.

 

Why do organizations keep backup communication methods?

Backup methods such as phone lines, secondary email accounts, or fax let teams keep working when their primary tools go down.