How to change Windows 7 log on background

1. Open the registry, go to the following key and change the value from 0 to 1:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Authentication\LogonUI\Background\OEMBackground

2. Take your picture, it is recommended to resize to your screen resolution. It has to be named backgroundDefault , its extension must be JPG and its size must not be more than 256KB!

3. Go to the following folder:
C:\Windows\System32\oobe\info\backgrounds
If you do not have the info or backgrounds folder, just create them. UAC might pop up, just click Yes.

4. Copy-Paste the picture in there. UAC might pop up, just click Yes.