Regarding usb gadget serial driver worked in Microsoft Vista

Dear all,

Recently, I have programmed a gadget serial driver,and it works well
in Windows XP,refering to the gadget_serial.txt document,such as the
following:
 expand C:\WINDOWS\Driver~1\i386\driver.cab -F:usbser.sys .

but, the driver could not work in Microsoft Vista, the command above
seem to not apply to vista,now, How to get this usbser.sys file from
Vista?

Or, Is there a document regarding how to use the gadget serial driver
in Vista rightly?
-- 
Wan z.s