My wallpaper changed when I changed some settings. What happed?

I was fooling around on my laptop. i changed a setting which i forgot and my wallpaper change to blue. So I changed it to a different wallpaper then it happend to change back and my original wallpaper shows up when i shut it down. HOw do i get rid of that!My wallpaper changed when I changed some settings. What happed?
if you selected a %26quot;theme%26quot; this might be the probem. you will have to go thru your settings and find out what you did.

streamreader

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