(2017-05-10, 5:59)yongxu wang Wrote: Really? I have re installed but I haven't found the propeller yet. Could you tell me where to download this part?Are you sure that you have only one library on your machine? maybe you updated a library but your editor uses another?
Otherwise, the part is avalable here http://www.ldraw.org/library/official/parts/89509.dat but you should not need to download a single official part if your library was healthy and properly configured.