Yea, try doing what Jam said, that usually works. Also check your administrator permissions in the control panel and if you do not have admin controls then that is prolly why. You should however have admin controls if you are the only one account on the PC. If not, then either give the controls to yourself or if you dont feel like it then live with a white background But the admin thing should work. Also again, try saving a picture from the net and then instead of going into the control panel, right click your desktop and then go into desktop and then, dont go into the wallpaper folder, try going into a seperate folder with pictures that you saved.

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What is a physical body. The body is merely an object. It is a form of existence far too impure to store the gods within us called souls. Now you will remember. The bloodstained history. Material desire. Hunger. Sexual Drive. Desire to dominate. Desire for fame. Humanity. As long as there is a body, desires will be born. The human ego will never disappear as long as desire remains present. Humans will continue to fight to fulfill their bodies desires and it will never end. At this rate there is no future.