Microsoft Teams down: Home office paralyzes the server of the communication tool

For some, the home office starts today due to the Corona crisis - for some using Microsoft Teams. Microsoft Teams is currently down in some cases and lets news, media, online status and calendar load for a very long time.
Some companies have switched to home office as of today due to legal regulations or to protect their employees. That seems to have been a bit too much rush for Microsoft: Microsoft Teams is currently down in isolated cases. Calendar, contacts, channels or the online status of the respective contact do not load. This means that some people are shown as "Status unknown" or "Offline".
Microsoft Teams down: The problem is being worked on
Numerous users have already reported on Twitter. So it's not up to you, it's Microsoft itself. I also have Microsoft Teams on twitter pinged. The problem is known and they are working on resolving it. Unfortunately, only the system administrator can see the exact cause - so the rest of the users just have to wait. Your IT department may be able to tell you more about the problem.
We're investigating messaging-related functionality proProblems within Microsoft Teams. If you are a system administrator, please refer to TM206544 in your admin center for further details.
- Microsoft Teams (@MicrosoftTeams) March 16, 2020