Ever wondered how to go about putting a photo from the gallery as the wallpaper for all flash or USB drive folders? Well, it's simple. You need to use different methods depending on whether you have a Vista operating system (OS) of Windows or XP OS. In the case of the former, place a picture with an extension of .jpg in the flash drive's root system and type code into the desktop file, before saving it with an extension of 'ini'. In the case of an XP version of Windows, the user should write the code and save it under the name 'desktop.ini', before refreshing the USB drive.