Select Manage Configurations using :

• Ribbon Menu   File   Configurations

Select a combination of basedatas from the lists. (the combination shows up in the description panel)

To unselect an item, hold Ctrl button down while clicking.

Select the line in the Description panel.

If the combination in the Description panel is black (existing), select Delete button.

Select OK button (observe! this removes the configuration for the hole implementation, also on all content)