I am using cIOS 36 rev 10 and doing something equivalent to: Code: IOS_ReloadIOS(249); fatInitDefault(); FILE* sd = fopen("sd:/whatever.txt", "wt"); fprintf(sd, "hello SD world\n"); fclose(sd); FILE* usb = fopen("usb:/whatever.txt", "wt"); fprintf(usb, "hello USB world\n"); fclose(usb); The problem is that the USB fopen will fail even though the SD open/write is OK. If I don't do the ReloadIOS both work. Any ideas / suggestions? I would really like to have USB writting with cIOS 36 rev 10. Thanks, Zapf Note I have also tried: Code: __io_wiisd.startup(); fatMountSimple("sd", &__io_wiisd); __io_usbstorage.startup(); fatMountSimple("usb", &__io_usbstorage); instead of fatInitDefault() to no avail.