I mean the one where you select an account and enter the password, not the lock screen.
Would be nice if I could have a picture there instead of a color as I do not like the colors that I can choose from.

Thanks in advance!

Method 1: The group policy is named Force a specific default lock screen image and can be found in this path in the group policy editor: Computer Configuration\Policies\Administrative Templates\Control Panel\Personalization

Method 2:

Press WinKey+I.

Select Change PC Settings.

At the top/right of the window, click the Lock Screen item.

Select any of the Thumbnail images to change to that image.

Click the Browse button and navigate to any custom image that you wish to use.

You can follow any method as your wish.

Hi,

As far as I kow, since Windows 8, user couldn't modify system login screen. Its backgroud is not a picture.