Show Login Screen after Restart



I have created a Robot System with multiple users. Beside the default user, I have added additional users, each with own grants. I can successfully login with each of them after log of.

The problem is, after powering on the robot controller, the system starts with the Default User Logged in, even after I reduced access level of the Default User. 

How to make after each restart, the Login Screen to be shown, so I can choose which user to log in?