Deleting "undeletable" objects
If you find you have an undeletable object, this trick sometimes (but not always) works.
1. Insert a floppy disk in a floppy drive.
2. Open the Drives object.
3. Drag the undeletable object to the floppy drive object. Make sure that you are moving the object (you can ensure this by holding the Shift key while dragging).
4. Format the floppy disk.
From My Cold, Wet Hands
10 minutes ago