What We Know About Microsoft's Outlook and Teams Outage

Microsoft's cloud-based 365 suite failed for thousands of business and enterprise users across North America on Thursday, cutting off access to email, Teams and other workplace tools for hours, according to the company's own status updates, reported by WIRED.

What happened to Microsoft 365 on Thursday?

At around 10:40 a.m. ET, Microsoft posted on its 365 status page on X that it was "investigating reports of users experiencing issues when accessing or using Microsoft Teams functionality in North America," WIRED reported. By just before 1 p.m. ET, the company said it was also aware of "issues accessing Exchange Online mailboxes through multiple connection methods in the Americas." Reports on the tracking site Downdetector spiked around noon before beginning to fall near 1:15 p.m. ET, according to WIRED.

Which services were affected?

Microsoft's status page listed Exchange Online, Microsoft Teams, SharePoint Online, Microsoft Copilot 365 and Microsoft Defender XDR among the services that may have been impacted, WIRED reported. A Microsoft spokesperson told the outlet in a statement: "We are aware and investigating reports of users experiencing issues with Microsoft 365 services, primarily issues with Exchange Online. We appreciate our customer's patience while we work to restore services as soon as possible."

What did Microsoft say caused it?

Microsoft said its network was "experiencing elevated load across multiple regions, which is likely contributing to the connectivity errors," but attributed the underlying problem to servers going offline rather than a surge in user traffic, according to WIRED's report. In a later post on X, the company said "a problem" was "causing servers to fail automated health checks and become unavailable." Microsoft said it had "paused all deployments," was "moving additional traffic off the affected infrastructure," and was "restarting affected servers to return them to service." The company added it had "begun redistributing connection traffic across our broader worldwide infrastructure to help balance the load" and was "aggressively pursuing all pathways to reduce impact."

Is this related to a cyberattack?

There is no indication a cyberattack caused the outage, WIRED reported. The outlet noted that cloud outages can stem from a range of causes, including configuration errors and Domain Name System resolution problems, but said none had been confirmed as the trigger in this case as of its report.

How does this compare to past Microsoft outages?

WIRED noted that major Microsoft outages are "relatively rare" but "far from unprecedented." In July 2024, a corrupted update from security firm CrowdStrike caused the "blue screen of death" on Windows machines worldwide, while a separate Microsoft Azure outage occurring at roughly the same time knocked services offline for hours, the outlet reported, adding that the two 2024 incidents were unrelated to each other despite their proximity in timing.

When will service be fully restored?

As of WIRED's last update, it was unclear exactly when the outage would be fully resolved or what specifically triggered the server failures. Microsoft's public statements indicated restoration efforts were ongoing, with the company rebooting systems and shifting network traffic in an effort to bring Exchange Online, Teams and related services back to normal operation for affected customers in the Americas.