Hi, good day!
- When was the last time it worked properly?
- Have you made any changes to your computer recently?
- What is the size in MB of the image you want to use as a background?
Press Windows key+R to open Run then copy and paste the path below.
%appdata%\Microsoft\Windows\Themes
Press Enter
In the resulting folder, delete the Transcodedwallpaper file and also the CachedFiles folder
Restart your computer
I look forward to receiving your update and I'm willing to collaborate with you till we resolve the issue. Do keep me informed by clicking "Add comment" below.