Can't recognize unallocated USB space

1. [window cmd console] diskpart

2. DISKPART> list disk

3. DISKPART> select disk 'the usb partition number'

4. DISKPART> clean

5. create partition primary

6. list partition

7. select partition 1

8. active

9. format fs=ntfs quick

10. exit

ref: http://liverex.net/65