Manage Hidden Computers

Manage Hidden Computers

I'm running Desktop Central 10.1.2127.5 with integration of ServiceDesk Plus. When I go to Agent > Computers I see an alert that says "Manage hidden computers to Desktop Central! You have 75 computers applicable for Desktop Central management. To enable management capabilities for the computer Click here."

I click the "Click here" link and see a list of computers. At the top I'm given the option that says "Select the computers that you want to provide Desktop Central product console and click Add".

There are machines in this list that we no longer have and I'd like for them to be removed from the list. How do I go about removing those computers?