This is intended for images that has been loaded on the controller by yourself. If the controller has no-lean image, you will not be able to remove those images included on the controller firmware.
Also Aroon, you cannot delete any image files that come *built-into* the controller.
As Daniel said, you can only delete AP images that YOU had previously manually loaded onto the controller. The others that came with the controller are NON-removable.
This is intended for images that has been loaded on the controller by yourself. If the controller has no-lean image, you will not be able to remove those images included on the controller firmware.