A major Microsoft outage on 1 March left tens of thousands unable to access key services like Outlook, Teams, and Office 365 for over three hours. Microsoft has not fully explained the cause but blamed a “problematic code change.”
Timeline of the Outage
Downdetector data shows issues began around 3:30 p.m. ET, with over 37,000 complaints for Outlook, 24,000 for Office 365, and 150 for Teams. Most reports came from U.S. cities like New York, Chicago, and Los Angeles, though users worldwide also experienced disruptions.
Frustrated users took to social media, with some initially fearing a hack.
Microsoft acknowledged the issue in a 4:34 p.m. ET update via its Microsoft 365 Status account, saying, “We’re investigating an issue in which users may be unable to access Outlook features and services.”
The outage affected more than just Outlook—Office 365 apps like Word, Excel, Teams, and Exchange were also down. In a follow-up post, Microsoft confirmed that “various Microsoft 365 services” were impacted and that engineers were reviewing telemetry and user reports.
By 5:00 p.m. ET, Microsoft identified a possible cause, and nearly an hour later, services started recovering. At 7:02 p.m. ET, Microsoft announced the issue was resolved after rolling back the faulty code. It advised users to check MO1020913 in the admin centre for details.
Ongoing Issues and User Frustration
Despite the fix, Microsoft’s service status page still showed ongoing issues with Outlook, stating, “We’re having issues, but we’re working on it.” Users expressed frustration, and businesses faced potential disruptions.
Since the incident started more than one hour ago, outage monitoring service Downdetector has received hundreds of reports, with affected users saying they’re also experiencing authentication problems.
Adam Pilton, Senior Cybersecurity Consultant at CyberSmart, says: “Many users are reporting that Microsoft 365 is down, and this appears to be multiple countries around the world. Lots of users are expressing their frustration at being unable to work, with no access to their emails, or important documentation and for some, they are simply unable to log in to their account.”
He says there is a suggestion that this has been caused by a recent code change by Microsoft to a portion of their infrastructure, however, this is yet to be confirmed by Microsoft.
“What we do know is that businesses around the world are being hampered, their ability to generate revenue is impaired and once again the businesses that have implemented continuity plans and prepared for the eventuality of Microsoft being unavailable, are the businesses that will weather this storm and will continue to generate revenue.”
While this may not be a cyber security incident, he says it is a timely reminder of our dependence upon third-party software and highlights the potential risks our businesses are exposed to.
Information Security Buzz News Editor
Kirsten Doyle has been in the technology journalism and editing space for nearly 24 years, during which time she has developed a great love for all aspects of technology, as well as words themselves. Her experience spans B2B tech, with a lot of focus on cybersecurity, cloud, enterprise, digital transformation, and data centre. Her specialties are in news, thought leadership, features, white papers, and PR writing, and she is an experienced editor for both print and online publications.
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