Unlike previous versions of Windows, Windows 7 lets you easily customize the Windows log-on screen. By editing a single registry value, you can change the current Windows log-on background image. The only caveat is that the new image must be less than 256KB in size.
To change the Windows log-on screen in Windows 7:
- Open the Registry Editor.
- Navigate to: HKEY_LOCAL_MACHINE Software Microsoft Windows CurrentVersion Authentication LogonUI Background.
- Double-click the DWORD key called OEMBackground and set the value to 1.
- Locate the new image you want to use and copy it to the %windir% system32 oobe info backgrounds folder.
- Rename the image to backgroundDefault.jpg.
- Restart your computer.
The Windows log-on screen should display the new image.