Microsoft outage: Teams and Outlook users left in the lurch worldwide. What happened?

A global Microsoft 365 outage reportedly disrupted vital services like Teams, Outlook, and Exchange, leaving thousands of users scrambling as businesses, calendars, and communications ground to a halt.

Reports of issues began surfacing overnight, with complaints spiking dramatically by 8 a.m. ET. 

By midday, outage tracker DownDetector registered over 5,300 complaints, with most users citing problems with Exchange and Outlook.

Microsoft, posting updates on X (formerly Twitter), attributed the chaos to a "recent change" and quickly began rolling back the update. “We’ve started to deploy a fix,” the company said, adding that “manual restarts on a subset of machines in an unhealthy state” were also underway.

By noon ET, the company claimed the fix had restored service to 98% of affected environments, but many users were still reporting delays in access to Exchange Online and Teams calendars. Acknowledging slower-than-expected progress, Microsoft stated that targeted restarts were ongoing.

While the company hasn’t revealed the nature of the problematic update, Monday’s outage coincided with the rollout of Recall AI, a new feature designed to store computer activity snapshots for enhanced searchability. The tool had previously faced criticism over privacy and security concerns, leading to its delayed launch.

This marks the second major Microsoft disruption in recent months. In July, a corrupted update caused a widespread system crash, impacting banks, airlines, and healthcare networks worldwide. That fix also required manual device reboots.

As businesses worldwide struggled to adapt, Microsoft offered no firm timeline for full restoration, leaving users anxiously refreshing their screens and searching for alternatives to their critical workflows.