How i sad, here is the solution:
First you have to dowload U-disk 1.45 or above. I used 1.45. Its worked fine.
1. Plug usb writer into your nds and hook it up till an empty usb slot on pc
2. HOLD A,B,L,R + Up on your nds to put the card into flash mode
(Screen will say USB SAFE BLOCK)
3...