The American group initially said it was investigating outage reports “in the Americas,” before clarifying that it had “confirmed that the issue could affect connectivity to the Microsoft 365 service for all users, in any region worldwide.”
Microsoft 365 is a service that bundles applications such as Outlook and Teams.
According to the outage-tracking site Downdetector, nearly 130,000 users reported problems with Outlook just after 6:00 p.m. GMT.
More than three hours later, about 50,000 users still said they could not access it, according to the site.
“We are relentlessly pursuing all leads to minimize the impact for users,” Microsoft said on X.
“We have paused all deployments, we are easing the load on the affected infrastructure and rebooting the affected servers to bring them back online,” she added.
The outage is also disrupting certain functions of artificial intelligence (AI) assistants that connect to Microsoft accounts to read emails or consult calendars.
Beyond Copilot, Microsoft’s AI assistant, Claude and ChatGPT were also affected: Anthropic and OpenAI, which develop them, reported that their AI assistants could no longer access Microsoft 365 services.
The outage is disrupting communications for many public services.
Deprived of email and voicemail, the University of Iowa’s hospital network had to ask patients to go through their online portal to reach their caregivers.
