Select the Desktop Wallpaper you like, if you are not sure of the size 800*600 will do nicely. When displaying the size you want Right Click your mouse over the image then Save Image As...a File or Set As Wallpaper. If you Set As Wallpaper you will lose it when you change your wallpaper. When you have Saved the Image in a place you will remember, go to your Desktop where your Icons live. Right Click your mouse on the Desktop Wallpaper then regular click Properties, this should open to Background just Browse for the File, click then Hit OK These are general instructions your OS should be similar.
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