Microsoft 365 Outage Enters Second Day as Recovery Continues
Microsoft says Outlook and Microsoft 365 availability is improving after a global outage that disrupted businesses, governments and hospitals.
Microsoft said Friday that availability of Outlook, Teams and other Microsoft 365 services is improving, but a global outage that began Thursday was still causing intermittent problems for some users, including delayed email delivery.
What happened
The trouble began around midday Thursday, Nov. 12, according to Gizmodo. ABC News reported that shortly before 1 p.m. ET Microsoft posted that it was investigating reports of users having trouble accessing their mailboxes. ABC News said Downdetector, a site that tracks user-reported outages, logged more than 100,000 reports within an hour of that post.
Microsoft first described the problem as an access issue in the Americas, then said users in any region could be affected, ABC News reported. The company paused deployments, moved traffic off affected infrastructure and restarted servers.
On Friday morning, Microsoft reported broad improvements in North America, sustained improvements in Europe and early signs of recovery in Asia Pacific, according to ABC News. Microsoft’s status page still showed degraded service for business and consumer Microsoft 365 users, Gizmodo reported. In a post on X, Microsoft said some users "may still experience intermittent access issues or delayed email delivery as recovery continues," Gizmodo reported.
Charles Lamanna, executive vice president of Copilot, Agents and Platform at Microsoft, told Gizmodo in an emailed statement that the company was seeing encouraging recovery progress. ABC News reported that he also said Microsoft regrets the disruption and that its teams are reviewing what happened and how to prevent similar issues.
What caused it
Microsoft has given differing explanations as the incident has unfolded, and the full root cause has not been publicly confirmed. According to Gizmodo, Microsoft said a large number of servers unexpectedly became unavailable, straining the remaining infrastructure, and that a process responsible for establishing secure connections became overwhelmed. The company rolled out a patch to improve server stability, Gizmodo reported.
ABC News reported that Microsoft later said the incident began with a problem during an earlier network capacity upgrade that surfaced after a recent network change. Both outlets reported that Microsoft said there is no indication of malicious or cyber activity.
Who was affected
Gizmodo reported that the disruption reached a wide range of organizations. Shipping company Maersk warned customers that emails and notifications could be delayed. Electric truck maker Workhorse Group postponed its third-quarter earnings release and investor call to next week. Bloomberg, as cited by Gizmodo, reported that apparel company PVH Corp., the owner of Calvin Klein and Tommy Hilfiger, saw some employee conversations in Asia about a planned workforce reduction of about 4% fail to take place on Friday.
Public bodies were also hit. The Los Angeles County Sheriff’s Department said email and other communication platforms were disrupted, and the Arapahoe County Sheriff’s Office in Colorado said online bond payments were affected, requiring in-person payment, according to Gizmodo. Employees of the city of Austin, Texas, could not send or receive email on Thursday, and Japanese government ministries used paper notices to tell journalists about schedules, Gizmodo reported. Some hospitals in the United Kingdom reported email disruptions, though Guy’s and St Thomas’ NHS Foundation Trust in London said its services were running as scheduled, the outlet said.
ABC News reported that New York City Emergency Management warned of delays reaching city agencies by email and advised residents to use alternative contact methods, call 311 for non-emergency services and call 911 for emergencies.
What comes next
Microsoft has said it addressed the underlying issue and is continuing to restore service for remaining customers and regions, according to ABC News. Email queues were nearing normal levels Friday, but intermittent access problems and delays were still possible.
It remains unclear exactly when all services will be fully restored, whether any emails were permanently lost, and how Microsoft will reconcile its differing explanations of the cause. Microsoft has said it is reviewing the incident, and a more detailed post-incident account has not yet been published.
