How can I change the Windows 7 Logon Screen wallpaper?

Is there an easy (and free) way to change the Logon Screen wallpaper in Windows 7?

If you don't want to do it manually, you can use the tweaks.com utility. I've used it on Win 7 Pro x64, works like a charm.

Here is a post from James O'Neil's blog at Microsoft Technet that explains how it can be done.

A few of people have noticed that I’m running Windows 7 with a customized logon screen, and a couple of them asked me if I used “logon studio” which (as I understand it) rummages round inside some of the image resources buried in DLL files.

In Windows 7 we have provided a registry key for OEMS to turn on custom backgrounds it’s under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Authentication\LogonUI\Background and the name is OEMBackground, you can add it if it isn’t there – it’s a DWORD 1 indicates use the custom backgrounds and 0 means don’t. Beware, if you change Windows themes this gets reset – which implies the theme covers the background as well.

Once the option is enabled you need to create files in the
%windir%\system32\oobe\info\backgrounds folder, the names are BackgroundHeightxWidth.JPG and BackgroundDefault.jpg so for this laptop I have a default and Background1920x1400.You can use this make your corporate Machine all more corporate or your personal machine that bit more personal. According the Windows 7 center where (I think) I first saw the tip the file size need to be under 256KB. If you want to customize the original background you find it’s named background.bmp in the OOBE folder (oobe for those who don’t know is Out Of Box Experience in Microsoft speak).