Setting up multiple monitors on Windows is quite simple and only takes a few minutes to do. Once you have set up multi-monitor mode (multiple monitors), you can set up individual wallpapers for each monitor. To do this, please refer to the article below from Network Administrator.
How to use separate wallpapers on different monitors in Windows 11
Windows 11 offers a number of pre-installed wallpapers to set as your desktop wallpaper. If you prefer a custom background, you can use a saved photo or download a high-resolution wallpaper from the Internet and set a different wallpaper for each screen.
To customize which wallpaper appears on which screen:
1. Press Win + I to open Settings.
2. Open the tab Personalizationthen click Background on the right.
3. Make sure the menu drops down Personalize your background is set to Picture.

4. Click Browse photos and select the image you want to set as your desktop wallpaper. Repeat the steps to add more photos.
5. Now, right-click on the image you want to set as your home screen background and select Set for desktop > Desktop 1. Similarly, right click on another wallpaper and select Set for desktop > Desktop 2. Repeat the steps for all your screens.

Additionally, you can configure and create a wallpaper slideshow in Windows 11 to automatically place different wallpapers on different screens. To do this, select the drop-down list Personalize your background and choose Slideshow. Then click Browse and select the photo album folder where your desktop wallpaper will be saved.
Once completed, Windows will regularly browse through the photos from the folder as a slideshow, at section Change picture according to each time period you choose.
How to set a different desktop wallpaper for each screen in Windows 10
Like Windows 11, you can set different desktop wallpapers for each display in Windows 10:
- Press Win + I to open Settings.
- Open Personalizationthen click tab Background.
- Click the drop-down menu Background and choose Picture.
- Click Browse and select the photo you want to set as your desktop background.
- Right click on the image you want to apply to your home screen and select Set for monitor 1. Similarly, right click on another image and select Set for monitor 2. Repeat the steps if you have more than two displays

Now, each screen in your setup will have a different wallpaper. If you like, select the option Slideshow to allow Windows to periodically set a new desktop background from your specified image album.
How to set a different wallpaper on each screen using Control Panel
You can use the menu Personalization and Appearance of the classic Control Panel to set the wallpaper for your screen. This is also convenient for installing wallpapers on non-activated Windows computers.
1. Press Win + R to open Run.
2. Copy and paste the following command and press OK.
shell:::{ED834ED6-4B5A-4bfe-8F11-A626DCB6A921} -Microsoft.Personalization\pageWallpaper
3. In Control Panel, click the drop-down menu Picture location and choose Windows Desktop Backgrounds.
4. You can use existing images or click on them Browse to import custom desktop wallpaper.
5. Right click on the image and select Set for monitor 1 or Set for monitor 2 to apply the background to either of your screens.

6. To create a slideshow, drag the cursor to highlight all the images you want to use, right-click any image and select Set as a slideshow.

That's how you use different wallpapers for each monitor in Windows 10 and 11. To keep your wallpaper from getting stale, consider turning on the slideshow feature to let Windows automatically set the desktop wallpaper new from your curated image album every hour, every day or every few minutes.
Wish you success!
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