The Controller Instance ID
This feature is always enabled when operating on Unattended Targets. Every time the Controller is started, controller generates a temporary and unique Controller Instance ID that is bound to the session being established. Only one Controller Instance ID can be bound to a session. Subsequent attempts to re-initiate the same session by re-starting the controller throws the error “the Controller Instance ID is invalid for the session.” The Controller Instance ID is not visible to the user.