Microsoft 365 hit by major outage, Claude services also disrupted

Microsoft 365 suffered one of its worst service outages in recent years. Exchange Online, Outlook, SharePoint, and some Teams services were down for nearly a day and a half. A Microsoft executive apologized and admitted the issue could not be fixed quickly.

Anthropic's AI assistant Claude was also affected. Anthropic reported that the Microsoft 365 connector had higher error rates and slow responses, so users could fail to access email, SharePoint, Teams chats, and calendars. Email and calendar actions in Claude for Outlook could not be done, and some users couldn't even open the add-in.

Meanwhile, Anthropic confirmed that claude.ai, Claude Code, and platform.claude.com saw unusual error spikes, and users could not complete sign-in on these platforms. The company said it is investigating.