I assume you are using Windows XP and you mean the Windows desktop background image is no longer being displayed.
If you have the image on your computer, find the file, right click on it and select .
If you don't have the original, look in:
C:\Documents and Settings\XXXXXX\Local Settings\Application Data\Microsoft
(XXXXXX is your login name)
You should find Wallpaper 1.bmp. Copy this into My Pictures so you know where a master copy is. Right click on it and select
(Obviously if there's more than one Wallpaper file, you'll have to do a bit of viewing to find the right one.)
Gruntfuttock, March 2010