You can set different wallpapers on different desktops in Windows 11/10 but you cannot set an image on one desktop and solid color or slideshow on another.

If you can't set different backgrounds for dual monitors on Windows 11/10 use this workaround or free tool to set different wallpapers.

Windows XP and Vista only: Dual monitor utility DisplayFusion can set different wallpaper images for each of your desktops or stretch an image across desktops.

To set different wallpapers on dual monitors in Windows 10, you'll need to go to your "Personalize" menu, which you can open with just a click.