Microsoft’s latest email outage turned into a full blown global cloud crisis

Summary

• Microsoft systems experienced a day-long outage caused by a cascading software issue that began on Thursday.
• The disruption initially affected services in the U.S. & the Americas before spreading globally.
• Affected services included Outlook email, Teams video conferencing, cloud services for consumer & business email, files, & documents, Copilot AI tools, Defender security software, & internal Intune dashboards.
• Some users reported issues accessing cloud-based Windows computers.
• Microsoft stated the outage involved a large number of servers becoming unexpectedly unavailable but has not identified the specific cause.
• Engineers initially struggled to find the cause of the server failures in Microsoft data centers.
• The outage impacted a broad range of industries, including TechCrunch's email services.
• As of Friday morning on the U.S. east coast, Outlook email service began recovering with emails trickling in.
• Internet traffic monitoring indicated services returned to normal after approximately 18 hours of downtime.
• Microsoft confirmed there was no evidence of malicious activity associated with the incident.
• The last major Microsoft service outage occurred in September due to a core authentication configuration issue.
• This incident was first published on November 12 & updated throughout the day.