I am going to walk you through the steps I use to customize the background of windows explorer. Because the files we are modifying are hidden we need to able to see them in windows explorer. From the menu in Folder Options in the View tab, select Show hidden files and folders and remove the check mark from Hide protected operating system files, you should now be able to see system hidden files.

The background image can be in the folder you are customizing or any other location you want. All you have to do is to provide the correct path, personally I put in

c:\windows\resources\backgrounds

but you can put it anywhere you want. Below are some links to websites where you can get nice background images.

www.dinpattern.com

www.squidfingers.com

www.k10k.net

www.playground.everydayicons.jp

www.kollermedia.at

Now create a file in the folder where you want to add a background and name it desktop.ini. You may find some folders which already contain a file named desktop.ini, in this case you just need to modify the file instead of creating a new one and just add the fallowing code to the top of the desktop.ini file.

[{BE098140-A513-11D0-A3A4-00C04FD706EC}] IconArea_Image=c:\path_to_image\image.jpg

Make sure that the path_to_image is the correct path to where you have the background images, and also that you have the correct image.jpg filename. I can also confirm that GIF, JPG, BMP formats work. All that is left is to save your file and refresh. I notice that when I added desktop.ini to a folder that did not contain one before, the background did now work. The way I got it to work, was to go to folder Properties under the Customize tab, select Change Icon and choose a different icon for the folder. This automatically fixed the problem.