Even after you delete a part, VisualAge might display a message indicating that instances of the part still exist.
If you get this message, do the following to delete all instances of the part:
<part name> allInstances do: [ : ea | ea become: nil ]
The code, when executed, sets all instances of the part to nil. After executing the code, delete the part.
For extensive information on deleting parts and on retrieving deleted parts, refer to the following: