Microsoft is struggling to restore its services following a widespread global outage that disrupted access to Outlook, Microsoft Teams, Copilot and other Microsoft 365 applications, with the company warning that its initial recovery efforts have not gone as expected.
The technology giant said in its latest service update that changes introduced to improve the affected systems had failed to deliver the expected results, prompting engineers to explore alternative measures to restore services.
“We’ve monitored the status of the changes applied to improve serviceability and confirmed that change is not taking as expected,” Microsoft said.
The company added that it was identifying alternative approaches to increase capacity amid continued imbalances in network traffic.
The disruption began on Thursday, November 12, and spread across multiple regions, affecting users in businesses, government institutions and other organisations that rely on Microsoft’s cloud-based services.
Outlook was among the worst-affected applications, with users reporting difficulties accessing inboxes, sending emails and receiving messages. Microsoft Teams, its workplace communication platform, and the Copilot artificial intelligence assistant also experienced connectivity problems.
According to outage-monitoring website Downdetector, reports of Outlook problems in the United States peaked at approximately 130,000. The disruption was reported in 74 countries and territories within about an hour, with users across the Americas, Europe, Asia and Africa experiencing problems.
What caused the outage?
Microsoft attributed the disruption to problems within its server infrastructure, where some servers became unexpectedly unavailable, placing additional pressure on the remaining operational systems.
The company subsequently identified an overwhelmed core process on affected servers that was contributing to capacity losses. Engineers attempted configuration changes, restarted affected servers and redirected traffic to alternative infrastructure in an effort to restore normal operations.
However, some servers that were brought back online became unresponsive again when they received traffic, complicating the recovery process. Microsoft also paused deployments while investigating the problem.
Microsoft executive vice president Charles Lamanna ruled out a cyberattack, saying the disruption was not caused by malicious activity or hacking.
The company has not provided a definitive timeline for the full restoration of affected services. It previously indicated that users could experience a gradual recovery as server capacity was restored and applications reconnected.
The outage highlights the widespread reliance of businesses and government organisations on Microsoft’s cloud-based infrastructure for email, workplace communication and other essential digital services.