When you login to your Windows 7 computer (assuming you haven’t used something like this tutorial to turn on automatic login), you’ll generally see a login window with a background looking something like this.
It’s fine; there’s nothing wrong with it. But sometimes a change is
good so in this article we’ll show you how to change the background
image behind the login screen to anything you want.
The first step is to open up the Start Menu by clicking the orb in the lower left corner of the screen.
Now, in the Start Menu search box, type regedit, to open up the Registry Editor.
When the Registry Editor appears in the Start Menu, click the Enter key to launch it. You should see a window like this.
Now, right-click on the HKEY_LOCAL_MACHINE folder, and choose the Find option.
The search window will appear so perform a search for OEMBackground.
It will eventually be found under Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Authentication\LogonUI\Background (you could navigate there directly, but the search function is probably quicker than typing all that into the path bar.
Note: it’s possible that OEMBackground doesn’t exist on your
system; if this is the case, adding a new DWORD value with the name of
OEMBackground will fix things.
Once you can see the
OEMBackground entry, double click to reveal its properties, and change
the value from 0 (the default) to 1 (which will allow us – or the
computer’s OEM as intended – to change the login screen background).
You’ll now need to create an info folder (all lowercase), and then a new folder, named backgrounds (also lowercase), inside the info
folder. Depending on your computer’s OEM, you may find these folders
already exist and may already have images in them, placed there by Dell
or HP or IBM, etc.
Now simply select a favorite wallpaper. It should be in JPG format and
less than 245 KB in size (and ideally the exact dimensions of your
display to avoid stretching). Name this image backgroundDefault.jpg and place it in the backgrounds folder.
You can now restart, lock your screen or logout to see your new login screen.
Congratulations! This isn’t the simplest process, and isn’t as simple as using a program like Windows 7 Logon Background Changer,
but if you want to get into the particulars regarding what programs
like that are doing, this is a good way to go, if a bit more complex.