On November 13th, Microsoft stated that the large-scale service outage, which lasted for nearly two days, was gradually being resolved. The availability of Outlook email accounts and other Microsoft 365 services, as well as the performance of email delivery, had improved, but some users may still encounter intermittent connection issues. The outage began on Thursday afternoon and affected businesses, government agencies, and other organizations around the world.

The outage affected multiple Microsoft services, including Outlook, Teams, Copilot, as well as Word, Excel, PowerPoint, SharePoint, and OneDrive. The network outage monitoring website Downdetector recorded nearly 130,000 related failure reports on Thursday afternoon. Local governments in Baltimore County, Jacksonville, and Austin in the United States were affected, and some government departments and the National Health Service (NHS) in the UK also experienced communication disruptions. Indian Airlines reported obstacles to customer service communications, and OpenAI and Anthropic also encountered issues related to connections with the Microsoft 365 service.

Microsoft stated that the issue mainly involved the Exchange Online infrastructure that supports the Outlook email and scheduling services. Some servers experienced abnormally high workloads, while others unexpectedly stopped providing services during automatic detection processes, resulting in connection disruptions for users. The company is working to improve services by restoring servers, redistributing traffic, and deploying software patches, as well as addressing the backlog of delayed emails.

At present, Microsoft has not yet determined the root technical cause of the failure, but stated that there are no signs that this incident was triggered by malicious activities or cyberattacks. The company is still working to restore the remaining affected systems, and the specific time when all services will return to normal has not been announced yet.