Outlook Outage Affects 130,000 Users

Microsoft experienced a widespread service disruption on Thursday that affected Outlook and other core platforms.

The outage peaked shortly after 1 p.m. ET, when Downdetector logged nearly 130,000 user reports of email access failures. Reporters noted that many users were unable to send or receive messages or load their inboxes. Issues also extended to Microsoft Teams, the Copilot AI assistant, and broader Microsoft 365 services.

Microsoft stated that it was investigating disruptions related to email and messaging applications. In an update on social media, the company acknowledged that users in the Americas were experiencing issues accessing Exchange Online mailboxes via multiple connection methods.

The tech company explained that a portion of its infrastructure was under elevated load. It identified that a number of servers were unexpectedly unavailable because they failed during automated health checks. Microsoft has not yet determined the root cause of that specific failure.

The company said it is testing a fix and implementing an alternative method for health checks to restore the impacted servers. A Microsoft 365 Status account posted on X that it is aggressively pursuing all pathways to reduce impact. Earlier in the day, Microsoft reported that it had successfully restored problems related to Microsoft Teams in North America, though some users continued to report connectivity issues.