Try this command
Converts FAT volumes to NTFS.
CONVERT volume /FS:NTFS [/V]
volume Specifies the drive letter (followed by a colon), mount point, or volume name.
/FS:NTFS Specifies that the volume to be converted to NTFS.
/V Specifies that Convert should be run in verbose mode.
EXAMPLES
convert d: /fs:ntfs - Convert the d: drive which in this example is a FAT volume to a NTFS volume. Note, if this volume is anything other than FAT, such as NTFS or RAW this command will generate an error.
Read about it here
http://www.computerhope.com/convert.htm#01