Microsoft Outlook, Copilot go down; users report missing emails

Microsoft's email and AI services, including Outlook and Copilot, went down Friday, leaving users unable to send or receive messages.

Reports of disruptions began emerging among South Korean users Friday morning, with many saying emails were not arriving. Microsoft attributed the outage to "infrastructure overload," though Microsoft Korea has yet to issue a separate statement.

According to Downdetector, an online service-outage monitoring site, a wave of reports about connectivity problems with Microsoft's Outlook email service began in the United States on Thursday (local time), followed by reports of issues with the AI service Copilot.

Downdetector said user reports suggested the problem likely lay with Microsoft 365, a cloud-based subscription platform that provides Word, Excel, PowerPoint, Outlook and other applications to both individual consumers and enterprise clients.

However, the site said there were "currently no issues" with Copilot.

Microsoft 365 is reported to have about 450 million business subscribers on paid plans and about 95 million personal and household users.

The outage also affected South Korea. Outlook email delays and outright delivery failures continued until around 9:30 a.m. Friday.

In some cases, emails sent at 5:30 a.m. Friday did not arrive until 8:04 a.m. the same day. Many users reported receiving no emails at all.

Microsoft said on SNS that the outage "has been confirmed to be caused by increased infrastructure load," adding that this was "believed to be the cause of connection errors." The company said it had begun recovery work, including rerouting access traffic to distribute the infrastructure load.

Meanwhile, Microsoft Korea has not issued a separate statement on the matter.