target does not reside on a known FAT device

    Facility: EFI$CP, The OpenVMS EFI Partition Control Program

    Explanation: the device specified for a FAT operation is not a
    recognized FAT device specification. The target is either not
    a FAT device, or not a FAT device that has been mounted within
    the current utility environment. This is incompatible with the
    command requirements.

    User Action: Respecify the command, with a corrected FAT device
    name or with a corrected FAT file specification parameter,
    or mount the target FAT device within the current utility
    environment.