Changing the logon background image in windows 7

Step 1: Use the following Group Policy setting.

-Start the Group Policy editor(gpedit.msc).

-Go to the following branch:

Comp.Configuration->Admin Templates->System->Logon

-Set the "Always use custom logon background" to Enabled.

-Close the Group Policy Editor.

Step 2: Next step is to place the background wallpaper(Jpeg File) in the following folder:

C:/Windows/System32/oobe/info/backgrounds

Note that the info folder does not exist by default, you need to create the info and backgrounds folder manually.

Place the background image file(name it as backgroundDefault.jpg) into the above folder.

The file size must not be more than 256 kb.