Problem

Neither the kpsadmin nor the managedomain utility allows spaces to be entered in the username, so an account with a name like "Test User" would not work. You will be unable to type a space when you try to enter the username.

Resolution

If you specify only the username on the command line (and not the password), both utilities will then prompt you for a password and work correctly. You can log in if you invoke the commands as:

kpsadmin -u "Test User"
managedomain --menu --username="Test User"