Extracting wallpapers

Guide to creating your own themes
For the really technical details of themes custom tweaking MSDN: Creating and Installing Theme Files

To choose pictures from existing themes you only need to find the folders where the themes are located. The images aren't embedded - they're just hanging out loose in a theme folder.
Look in these locations:
C:\Windows\Web\Wallpaper
C:\Users\your-name\AppData\Local\Microsoft\Windows\Themes\
 
Solution

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