If you are running the Pro or Business editions of Windows, you can use the Group Policy Editor. But if you are using a Home edition of Windows, you will have to do is edit the Registry. Let us see how to do it.
Prevent Users from changing the Screensaver
Using Windows Registry
Open the Registry Editor by hitting Start and typing “Regedit.” Now, in the Registry Editor, use the left sidebar to navigate to the following registry key for disabling screen saver settings for the currently logged in user: If you would like to disable screen saver settings for all users of the same PC at once, navigate to this key: Apart from the hive, everything about those two locations is the same. The basic difference between the two is while items in HKEY_LOCAL_MACHINE apply to all users, items in HKEY_CURRENT_USER apply only to the currently logged-in user. Once there, look for “System” entry under the Policies key. If you do not find, you’ll need to create one. To do so, simply right-click the Policies key and choose New > Key. Name the new key “System.”
Create a new value inside the System key by right-clicking in the right side and choosing New > DWORD (32-bit) Value. Name the new value as “NoDispScrSavPage”.
Thereafter, double-click the new value to open its properties window and change the value from 0 to 1 in the “Value data” box.
Click “OK” and close the Registry Editor.
Using Group Policy Editor
Run gpedit.msc to open the Local Group Policy Editor and navigate to the following setting:
On the right side, double-click the Prevent changing screen saver setting to open its Properties window. Select Enabled, click Apply and exit. That’s it! The changes made by you can also be reversed. Try this and let us know if the method works for you. TIP: Points 4 & 5 of this post will show you how to prevent changing your Desktop background wallpaper.