Microsoft: Problems with mail, AI and calendar - recovery is ongoing

What is known about the failure - and what is not? The overview.

What happened?

Microsoft users not only report problems with the Outlook email service, but generally with services from the Microsoft 365 cloud package:

The calendar connection does not work properly with the Teams office communication offer. Meetings are not easy to plan.

In addition, the AI ​​assistant Copilot, the management portal for administrators and interfaces to third-party providers - including AI services such as those from OpenAI and Anthropic and other services - were temporarily disrupted.

How many people are affected?

It is still unclear how large the extent of the failure really is. According to the Downdetector platform, which operates under the name Alletreib in Germany, Microsoft services were affected in 74 countries and regions. At times, around 130,000 fault reports were received in the USA for the Outlook email service alone. The actual number of those affected is likely to be significantly higher, as Downdetector is based on reports from users. According to the company, more than 430 million people use Microsoft 365 apps worldwide.

Over the course of the morning, the number of fault reports for Downdetector and All Faults continued to decline. At the same time, several companies in Germany are giving the all-clear. Deutsche Bahn and Lufthansa, among others, announced that the Microsoft disruption had no impact on train and air traffic.

What is known about the cause?

Microsoft commented on the outages in messages on Platform X and on its own website. Initially, problems with Exchange mailboxes in the USA were reported. The company then warned that the disruption could affect connections to Microsoft 365 services worldwide.

According to Microsoft, there is no evidence of a cyber attack. Instead, there is talk of an "increased utilization" of the infrastructure - numerous servers were "unexpectedly unavailable," according to the company. This “probably contributes to the connection errors.” “We are aggressively pursuing all options to reduce the impact.”

How are the recovery efforts going?

After initial attempts at a solution apparently did not work as expected, the company reported “gradual improvements” around 11:30 a.m. German time. The recovery measures would progress "in phases," it said on X. At the same time, the capacity of the services had "not yet fully returned to the initial value."