Windows 7 Logon Background Changer can customize your welcome screen wallpaper. It is a free open source software that let you change the wallpaper of the Windows 7 logon screen (also known as "welcome screen", "login screen" or LogonUI).

Windows 7 Logon Background Changer has been tested successfully with the final version of Windows 7 (RTM) and Windows 7 RC 7100. It works with Windows 7 Home Basic, Home Premium, Professional, Ultimate and Enterprise, in x86 or x64 (32 or 64 bits). It does NOT work with Windows 7 Starter (edition sold with most netbooks). It works also on Windows Server 2008 R2 (but you are not supposed to customize a server).

The Windows 7 Logon Background Changer application was designed to be a free open source software that lets you change the wallpaper of the Windows 7 login screen. It has been tested successfully with Windows 7 RC 7100, but it should also work with future releases.

On a side note, this small program is WPF based, it's a nice technical demo of Windows Presentation Foundation capabilities for those interested in WPF. It requires a decent GPU for the 3D animations to run smoothly. It runs fine with my Radeon HD 3200 on my laptop computer, but it should also work with lower end graphic cards, albeit slowly.

What does it do?
1. It does NOT change any system file, and the program itself does not requires admin rights to run : it will just ask you to run as admin a very simple cmd file that creates the required folder and registry key with the appropriate rights. Any user of the computer will then be able to change the Windows 7 logon screen wallpaper. You can also prevent users from being able to change the logon screen wallpaper if you don't want them to be able to modify it without administrator rights (option available by clicking on the "Settings" button).
2. It creates a few JPEG files based on the image you want to put as wallpaper for the Windows 7 login screen, applies the appropriate cropping and sizing and saves them using the best compression quality possible.

To use this application, you can:
-Run it directly by opening Win7LogonBackgroundChanger.exe
(right click on it, and run it as administrator if you don't want other users of this computer to be able to change the logon background later)

OR
-If you prefer to install it, run setup.exe.
To open the app once it is installed, go to Control Panel, Appearance and Personalization, or use the shortcut in the start menu.

The license of this software is Freeware, you can free download and free use this system optimizer software.