Overview

This article outlines the steps required to change the background image of a computer when you are trying to log into it.  Using these steps you can display an image behind the log in screen as a reminder to the users. This background can be found under C:WindowsSystem32oobebackground.bmp and is shown in the screenshot below.

Default Window’s Background

Customize Your Windows 7 Login Background

1. Open up your run command. (Fastest way to do is to do ‘Windows Key’ + r)
2. Type in regedit.

   
    

3. Find HKEY_LOCAL_MACHINE > Software> Microsoft > Windows > CurrentVersion > Authentication > LogonUI > Background
4. Double-click on OEMBackground
    
5. Change this value to 1. 

   

6. Click Okay and close out of regedit.
    
7. Open up Windows Explorer or My Computer and navigate to your Windows directory.
    
8. In your system32 folder in your windows directory, you’ll need to create a couple new folders. For the standard user, go to c:windowssystem32oobe and create a folder labeled info. Inside the info folder, make another folder called backgrounds.

   Your final path should look like c:windowssystem32oobeinfobackgrounds
    

9. Place your image in this folder. Note 2 important things:
   • 1st: Your file must be labeled backgroundDefault.jpg
   • 2ndly: According a handful of sources, your file must less than 256kb in size, but I have never been able to successfully implement a background unless it was less than 250kb in size.
10. To test if your background is working correctly, lock your computer with ‘Windows + L.’ Your image should now show up on your Windows Login screen.
11. Alternatively, name your background to work with specific resolutions. Here are the background names:
    • background768×1280.jpg (0.6)
    • background900×1440.jpg (0.625)
    • background960×1280.jpg (0.75)
    • background1024×1280.jpg (0.8)
    • background1280×1024.jpg (1.25)
    • background1024×768.jpg (1.33-)
    • background1280×960.jpg (1.33-)
    • background1600×1200.jpg (1.33-)
    • background1440×900.jpg (1.6)
    • background1920×1200.jpg (1.6)
    • background1280×768.jpg (1.66-)
    • background1360×768.jpg (1.770833-)

Additional Sources Used for Step 11.: http://www.blogsdna.com/2698/you-can-customize-windows-7-logon-background-officially.htm