Microsoft is gradually recovering from a massive service outage that lasted a day, TechCrunch reported on Nov. 13 local time.

The outage began on Nov. 12, the report said. It was initially believed to have affected services in the United States and the Americas, but it spread worldwide as engineers failed to restore the stopped servers.

The outage began with Outlook email and Teams videoconferencing and expanded to other services. Users were unable to access Microsoft 365, Outlook, Teams and OneDrive.

Both individual and corporate users were unable to use cloud-based email, files and documents. Copilot and Defender security software also went down. System administrators could not access internal management tools, including the Intune dashboard and functions. Some users also experienced problems accessing cloud-based Windows PCs.

Outlook began to recover from the outage as of the morning of Nov. 13 Eastern time, and some email services are being restored, TechCrunch reported. Doug Madory, Kentik's director of internet analysis, said traffic is returning to Microsoft services after about 18 hours of disruption.

In its latest notice on Nov. 13, Microsoft said there was no evidence of malicious activity related to the incident.

It also said the cause was not AI but an incorrect network upgrade. Microsoft said the outage was a technical problem unrelated to a cyberattack or AI agents, and that an issue that arose during an earlier network capacity upgrade surfaced after recent network changes. It said the root cause had been addressed and it was continuing to restore remaining services.

TechCrunch said Microsoft could face criticism for failing to restore the outage quickly, as it was caused by an internal issue rather than an external attack.