Unable to store file in Windows CE on smart210

I have been faced some problem with Windows CE .NET 6.0 on smart210.
When I transferred file into any directory, such as My Document, it will
stored until I delete or power-off the system.
When I power-on again, the file have been disappeared.

How to store it on smart210?


you should copy file in NANDFlash(My Device\NANDFlash)