Microsoft Outlook Hit with Worldwide Outage

Microsoft's Outlook service went down for about 12 hours on Feb. 6, according to the company. 

The 12-hour estimate may not be what Outlook users experienced. It's based on Microsoft's Twitter posts for the incident, labeled "EX512238." Microsoft first indicated that it was "investigating" Outlook issues on Feb. 6 at 8:26 p.m. (per the Twitter message timestamp). Microsoft subsequently stated that the issue had been resolved on Feb. 7 at 8:45 a.m.:

We've confirmed that the issue is resolved after an extended period of monitoring. Further details can be found under EX512238 and TM512245 in the admin center.

Admin Center access to Microsoft's more detailed incident reporting is restricted to IT pros with Exchange Online management roles in organizations. However, Exoprise, a company that uses "synthetic sensors" (headless browsers) to detect service outages, offered a few more details in this Feb. 7 Exoprise blog post.

Exoprise's sensors detected two Outlook outages, one occurring at 11:03 p.m. (London time) and another at 2:00 a.m. Exoprise didn't provide a total time estimate for the outage, nor did Microsoft in its Twitter posts. The outage affected Exchange Online e-mail services in North America and worldwide, with people unable to "send, receive or search e-mail," according to Exoprise's blog.

Microsoft initially ascribed the root cause of the incident to a problem routing e-mail traffic.

"Root cause: A subset of infrastructure, responsible for routing traffic, unexpectedly stopped responding to traffic requests," Microsoft indicated on Feb. 6.

The issue was further described on Feb. 6 as due to "a recent change that may be causing issues with send, receive, or email search within Exchange," although the change wasn't described.

About the Author

Kurt Mackie is senior news producer for 1105 Media's Converge360 group.


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