Set Wall Paper In Your Pen Drive, Drive, Folder

Copy the following code and paste it in note pad

[{BE098140-A513-11D0-A3A4-00C04FD706EC}]
IconArea_Image=PATH_OF_THE_WALLPAPER

Save the file as desktop.ini and see the changes

Note:- If the wallpaper exist in the same folder then write the full name of the wallpaper.