Lock screen image change in Windows 10

I need to change the Lock screen image.

By default, "Windows spotlight" is selected.

Is there a way to change this to "Picture" using the registry settings (regedit)?

Tried below things:

Set LockScreenImage = "C:\Windows\Web\Screen\img100.jpg" @ HKLM:\Software\Policies\Microsoft\Windows\Personalization

Placed the image what to be displayed in lock screen at:

C:\WINDOWS\Web\Screen\img100.jpg. 

New users are getting this img100.jpg at the lock screen but not for the current user.

And also if we change to "Picture" at Personalization -> Lock screen -> Background, then img100.jpg is getting selected and set at the lock screen.

Solution 1:

Scrapping my previous answer, since I see you want to do it via Registry. That's a terrible idea, registry hacking is always a last resort, since it breaks so easily. All I can say is good luck; the key you want is HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Lock Screen, but the format is completely opaque, and that's not all: The actual lock images are stored in a folder C:\ProgramData\Microsoft\Windows\SystemData\{SID}\ReadOnly\LockScreen_B, which is normally secured for SYSTEM only.

Forget the registry, just use Powershell to call the API; you can easily set it in 2-3 lines.