Customizing Your Win 7 Logon Screen

The easiest way to change the default logon wallpaper is to use Local Group Policy Editor

1. Open the Local Group Policy Editor by Cmd + R, and enter gpedit.msc
2. Go to Computer Configuration > Administrative Templates > System > Logon
3. Enable the option of Always use custom logon background
4. Click OK / Apply button and close the editor
5. Open windows explorer, go to and create a directory - C:\Windows\System32\oobe\info\backgrounds
6. Put your desired background as backgroundDefault.jpg under the directory while your image size must be less then 256KB
7. Done ! Try to Cltrl+Alt+Del to see the result.

You may also enable the option by editing the registry instead of group policy. Details can be found at http://www.winhelponline.com/blog/windows-7-lets-you-change-the-logon-background-image/