You can only delete a set that is not used in documents and that is not linked to any product.
To delete a set:
- Select the set you want to delete in the right part of the Sets window
- Use the Delete set context menu item or the Document > Delete set main menu item
- The system will ask you to confirm the deletion. Click Yes if you really want to delete the selected set. Click No if you mistakenly selected the Delete set menu item.