As far as i know, writting C64 disk with an pc 5.25" drive doesn't work. Once i had a cable someone made for me, to connect a 1541-II via serial port with my 486. Last year i wanted to backup some C64 stuff from my old disks and just bought a XU1541 interface from ebay to connect my 1541-II via USB with my laptop. Worked perfectly. Does this answer your question?