Why do I receive an error message "AADSTS90100" or "AADSTS90019" when I try to sign in?

If you have different Microsoft accounts, such as a private Hotmail/Outlook account or a Microsoft 365 account with your employer, there may sometimes be a conflict between those accounts that prevents you from signing in. The error message you receive looks similar to the following:

FAQ Image

It can read: "AADSTS90100: login parameter is empty or not valid" or "AADSTS90019: No tenant-identifying information found in either the request or implied by any provided credentials."

This problem can be solved in different ways:

Method 1
The first thing you can do is go to https://office.microsoft.com and see if you can switch to your @du.se account.

Method 2
Try signing in with a different browser

Method 3
Try logging into a private window. How to do this depends a little on which browser you are using:

Method 4
Some browsers offer the ability to separate your different accounts into different profiles in your browser. How to do this depends on the browser you are using:

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