Change windows 7 login Background

Step 1: Open the Run dialog box and type regedit

Step:2 

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Authentication\LogonUI\Background. If the key does not exist, add a new DWORD value with the nameOEMBackground.

Step: 3 Double click on the entryOEMBackground, and change the value from 0 to 1

Step: 4 Open C:\windows\system32\oobe.

Step: 5 create a new folder namedinfo, and open it.

Step: 6 Create a new folder withininfonamedbackgrounds.

Rename your desired wallpaper asbackgroundDefault.jpgand place it inside the folder backgrounds (images must be less than 245KB in size).

Other Way

First download the free application here, run it.

Change Logon Screen” lets you browse to a new image, “Test” will bring up your logon screen