Microsoft says fixes fall short as Outlook outage drags on

A Microsoft ↗ 0.36% 365 outage cut off access to Outlook email, Teams and Copilot for business users around the world on Thursday, Nov. 12. Hours after it began, Microsoft said its fixes so far had "not provided the anticipated relief." Close to 130,000 users reported problems with Outlook on Downdetector just after 1 p.m. ET, AP reported. By early evening, Microsoft still had not said when service would be fully restored.apnews.com

What broke

Microsoft first said shortly before 1 p.m. ET that users were having trouble reaching Exchange Online mailboxes in the Americas. It later warned that users "in any region" could be affected, according to Insurance Business. Its service health alert listed Exchange Online, Teams, SharePoint Online, Copilot and Defender XDR as potentially affected. Mashable noted that the problems hit business and enterprise customers, and that Microsoft's own status page was down for part of the day.insurancebusinessmag.com+1

The company said the strain on its systems "isn't caused by a spike in traffic, but rather by several servers being unexpectedly offline, putting pressure on the remaining infrastructure," the BBC reported. Those servers were failing automated health checks. Microsoft said it had found no recent change that lined up with the start of the outage, but that the failures might come from a specific component on the servers that processes those checks, according to Fox Business.foxbusiness.com+1

A recovery that stalled

"We're aggressively pursuing all pathways to reduce impact," the Microsoft 365 Status account wrote on X. The company said it had paused all deployments, moved traffic off the affected infrastructure and was restarting servers, AP reported. At about 4 p.m. ET, Microsoft said an alternative health check method had let a subset of affected servers come back online. It said it was rolling that change out more widely and preparing automated systems to find and restart servers that stop responding, according to the Miami Herald.miamiherald.com+1

The progress did not last. In a 5:09 p.m. ET post, Microsoft said it was "opening all available pathways to restore service, as our actions taken thus far have not provided the anticipated relief," and that "a core process on affected servers is becoming overwhelmed, causing capacity loss," The Oklahoman reported. The company said it would isolate part of its infrastructure, restart affected components and bring traffic back gradually to check that services stayed stable before applying the change more broadly, according to NBC Chicago.oklahoman.com+1

Lingering disruption

Reports fell from the midday peak but did not go away. Just before 5:30 p.m. ET, about 38,000 Outlook users were still reporting problems on Downdetector, The Oklahoman reported. Some users found their inboxes would not load, while others could not send or receive mail, according to The Seattle Times. A Microsoft spokesperson told the paper, "We appreciate our customers' patience while we work to restore services as soon as possible." Mashable reported that Microsoft had still not given an estimated time for recovery.seattletimes.com+2