Microsoft 365 Outage Knocks Outlook and Teams Offline for Thousands
Microsoft services including Outlook and Teams experienced a widespread outage whichm affected users across North America, resulting in multiple users losing their ability to send emails and access their accounts and use essential office applications.
Microsoft 365 users experienced widespread service disruption which affected their ability to use the platform. Down detector data showed tens of thousands of reports, especially tied to Outlook access issues, and users described problems that made normal work communication difficult.
Microsoft confirmed the outage through a public statement which explained that its team was investigating an issue that affected multiple Microsoft 365 services.
- Outlook
- Microsoft Teams
- Microsoft Defender
- Microsoft Purview
Microsoft later attributed the outage to a malfunction in part of its service infrastructure that processes network traffic. The company said it restored the affected infrastructure to a healthy state, but still needed additional work to balance system load and fully stabilize services. Users reported seeing specific email-related error messages, including 451 4.3.2 temporary server issue.
Microsoft recovered from the situation by rerouting network traffic to healthy infrastructure while recovery activities were in progress.
Quick summary of what happened
- Outlook and Teams were impacted heavily
- Businesses and individuals could not reliably use Microsoft 365 services
- Microsoft confirmed infrastructure issues and began mitigation
- Some services returned gradually, but full stability required load balancing