More than 130,000 Outlook problem reports surfaced on Downdetector shortly after 1 p.m. ET on Thursday, Nov. 12, as a widespread Microsoft outage disrupted workplace communication tools globally.
The disruption hit right in the middle of the workday, affecting Microsoft 365 services across 72 countries, according to Mashable India. Users reported trouble accessing their email accounts, sending or receiving messages, logging in, and connecting to applications such as Microsoft Teams, SharePoint, OneDrive, and the AI assistant Copilot.
The issue was tied specifically to Exchange Online, Microsoft’s cloud-based email platform that powers Outlook and other connected productivity tools. Administrative features including Microsoft Defender XDR, Planner, To Do, and Intune also experienced problems.
While we're working to mitigate impact, we've confirmed the issue may affect Microsoft 365 service connectivity for users in any region, more information will be provided in the Microsoft 365 admin center under EX1550543.
Microsoft identified connectivity errors affecting the infrastructure used to receive mailbox access requests, logging the incident as EX1550543. Affected connection methods included Outlook on the web, MAPI, Exchange ActiveSync, and REST APIs. The company initially reported problems accessing Exchange Online mailboxes in the Americas before confirming that the disruption affected users in any region.
Microsoft attempted a targeted configuration change to redistribute traffic, but servers were unavailable.
We're aggressively pursuing all pathways to reduce impact. We've paused all deployments, we're moving additional traffic off the affected infrastructure, and we're restarting affected servers to return them to service. More info under EX1550543 and MO1550821 in the Microsoft 365…
“We're working to safely return them to service,” Microsoft said.
By Friday, Microsoft reported that recovery efforts were not going as well as expected, with problems continuing in Asia and Australia. Australian Home Affairs and Cyber Security Minister Tony Burke addressed the incident at a news conference.
They believe they are dealing in some ways similar to what we saw with respect to CrowdStrike where there is an update that has gone awry.
Minister Tony Burke, Australian Home Affairs and Cyber Security Minister
“The impact that they are dealing with … is very much on email systems,” Australian Home Affairs and Cyber Security Minister Tony Burke added, and said that Australia's spy agency and federal police were among the organizations caught up in the outage. Microsoft said that the incident was not believed to be due to a cyberattack.
Other technology companies felt the knock-on effects. OpenAI reported investigating broken Microsoft connectors, while Anthropic said that an issue with an upstream provider affected its Microsoft 365 connector. Workhorse Group, a US-based truck and bus manufacturer, postponed its earnings announcement from Thursday to Monday because of the outage, and schools, universities, and hospitals warned that communication services were limited.
Microsoft reported achieving a partial recovery of services in certain regions, but its measures had not ensured sustained recovery. The company stated it was reviewing additional actions to improve overall infrastructure stability.
More on Exchange Online
Discover more from Archyworldys
Subscribe to get the latest posts sent to your email.