Major Microsoft 365 outage left users without access to emails and files – here’s what we know

• MO1221364 Microsoft 365 outages have now been fixed
• Microsoft says parts of its North American infrastructure were to blame
• Hours of rebalancing and refining preceded a fix, but it seems to have worked

A widespread Microsoft outage disrupted access to core M365 services for enterprise customers, as email inboxes, files, meetings and other cloud-based tools were all restricted.

“We are investigating a potential issue affecting multiple Microsoft 365 services, including Outlook, Microsoft Defender, and Microsoft Purview,” the company wrote in an X post that identified the issue as MO1221364 in the admin center.