Also, you can get more info about what to do when you receive the “ That Microsoft account doesn't exist” message when you try to sign in to your Microsoft account. If you're having issues signing in to your account, see When you can't sign in to your Microsoft account for help.
If you're an administrator, you can find more information about how to set up and manage your Azure Active Directory (Azure AD) authentication environment in the administrative documentation for Azure Active Directory.
