Hello ErnestNtshetho-4970,
Thank you for posting in our Q&A forum.
I think it should work if you followed the steps in the link https://techexpert.tips/windows/gpo-configure-wallpaper/ you provided.
Or you can try the following troubleshot steps:
1.Uncheck the option Archive.
2.Change destination file to C:\Users\%Username%\Pictures\TEST.jpg
3.And then check the gpresult result on one PC to see if the gpo takes effect.
3-1.Logon the PC using the specific domain user.
3-2.Open CMD (do not run as Administrator)
3-3.Type goresult /h C:\folder1\gpo.html and click Enter.
3-4.Open gpo.html and check the two gpo settings under "User Details".
User Configuration > Policies > Administrative Templates > Desktop > Desktop
Enable Active Desktop and Desktop wallpaper.
AND
User Configuration > Preferences > Windows Settings > Files
Hope the information above is helpful. If you have any question or concern, please feel free to let us know.
Best Regards,
Daisy Zhou
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