galvao@galvao-desktop ~> sudo ntfs-3g /dev/sda1 /mnt/point
NTFS signature is missing.
Failed to mount '/dev/sda1': Invalid argument
The device '/dev/sda1' doesn't have a valid NTFS.
Maybe you selected the wrong device? Or the whole disk instead of a
partition (e.g. /dev/hda, not /dev/hda1)? Or the other way around?