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:

  1. Open the Registry Editor.
  2. Navigate to: HKEY_LOCAL_MACHINE Software Microsoft Windows CurrentVersion Authentication LogonUI Background.
  3. Double-click the DWORD key called OEMBackground and set the value to 1.
  4. Locate the new image you want to use and copy it to the %windir% system32 oobe info backgrounds folder.
  5. Rename the image to backgroundDefault.jpg.
  6. Restart your computer.

The Windows log-on screen should display the new image.