When you enter Windows 8, you see the Lock screen followed by the Sign-in screen
In the past I wrote a couple of articles about changing the Logon screen wallpaper in Windows 7 and it appeared to be a very popular topic. In Change and customize Windows 7's Logon screen wallpaper, I showed you how to do it by editing the registry and in An awesome tool for customizing the Windows 7 Logon screen wallpaper, I showed you how to do it with the Windows 7 Logon Background Changer. Well, recently I've been hearing from readers wondering if there was a way to change the logon screen background in Windows 8. Well, the answer is Yes and No.
To begin with there are actually two screens that you see when you enter Windows 8 and neither of them is actually called the Logon screen. When you turn on a Windows 8 system, you first see the Lock screen, which prominently displays the time and date, and then you see the Sign-in screen, which displays the user account(s) and prompts you to enter a password. These two screens are shown in Figure A.
Credit: Images by Greg Shultz for TechRepublic