Microsoft Office 365 investigated an outage Saturday that left tens of thousands of users unable to access Outlook, according to an outage tracker. "We're investigating an issue in which users may be unable to access Outlook features and services,

Thousands of Microsoft 365 customers reported having issues with services like Outlook on Saturday. In a series of posts on the social platform X, the company said it was investigating the issue, which affected various Microsoft 365 services.

Thousands of users reported not being able to use their Outlook email or make calls on Teams before noon on Monday. Microsoft said a fix had begun to restore service for users by Monday afternoon.