my son has an MP3 player, memorex type, model MMP8570. It worked fine for about a month. Without any reason, my son turns it on and it says: "Incorrect Format. Please REFormat the player." I have tried everyting, including using the disk that came with the product, to no avail. my system is operating Windows XP. The format feature under windows explorer doesn't work either. any help, advice would be greatly appreciated.