Windows 7 allows admin to activate a feature that prevents users from changing the wallpaper of the computer.
How To Prevent Users from Changing Wallpaper
To restrict users from changing the wallpaper (under your Administrator account), click on Start
> type gpedit.msc
and press enter
Next, go to Local Computer Policy
> User Configuration
> Administrative Templates
In the right pane, select Desktop wallpaper
Indicate the full path for your custom/default wallpaper. Center and stretch the image as required and press the OK
button to validate.
Now, restart your PC to check the results.
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