I have written a image on the usb by the win32diskimager,before I press write it said that writing to a physical drive may curropt the drive,i thought it may also not corrupt so i pressed write,after finishing my work with the usb,i format it but after formating the usb properties says 'usedspace-0 bytes freespace-256mb',how can a 2 gb flash drive change into 256 mb flash drive.?please help me how can i fix it ?is there any way to make it as like as before again ?