Rumors have been going around and I’ve done my research. As of build 7057 (I’ve already upgraded before testing this), you can easily change the background of the log-in screen. Many people have commented that the current background is quite ugly, and if you’re one to agree, then in these 2 easy steps we’ll fix that.

What you need:
A picture, in jpeg format, roughly in the dimensions of your monitor. We’ll go the easy way so the more your picture is off, the more it will be skewed.

Step 1: the registry
Don’t be scared. It’s not as hardcore as the other usual edits you hear about. Open ‘regedit’ from run in the start menu. Dig through the directory tree on the left, something along these lines: HKEY_LOCAL_MACHINE – SOFTWARE – Microsoft – Windows – CurrentVersion – Authentication – LogonUI – Background
There you’ll find in your main window a registry file called OEMBackground, double click this, and change the value to 1 (one). Close the registry editor, and move to step 2.

Step 2: placing the image
Now it’s time to place your image into the correct location, and create that location if it doesn’t already exist. Go to your Windows folder, usually on the C drive, and find the directory: System32 – oobe. If don’t see a folder called info, create it, and put a new folder inside there called backgrounds. If you’ve already got these folders, have a look inside and just replace these images with yours. (This was not the case for me, so I have no experience with that particular case). Now take your image that you’ve prepared before, and copy it into this new backgrounds folder. Rename the image to backgroundDefault.jpg, and make sure the size is no bigger than 256 Kb (rumors on the internet say it won’t work otherwise).

Now the easiest way to test it is to lock your computer. Hold the Windows Logo key and press L, and you should see your new background! Many other websites will have you reboot your computer, but c’mon, if you want to test out 50 different images, that’s going to take a long time!

So, I hope I’ve improved somebody’s life somewhere by writing this, enjoy Windows 7 (while you can [read: while it’s still free])!