Windows: Change logon interface Background

Open

HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows \ CurrentVersion \ Authentication \ logonui \ background \

If no oembackground exists,
Double-click your "oembackground" key value. By default, the value here is "0", and the key to enabling the background of the custom Windows 7 logon interface is here, change "0" to "1 ".
Place the image to be used as the background of the login interface to the system's specified path c: \ windows \ system32 \ oobe, create a folder named "info" (without double quotation marks), and open the info folder, create a new folder named "backgrounds" and put the image as the background of the Windows 7 logon interface in the "backgrounds" folder. Restart your computer.
Note: first, the image must be in JPG format. Second, the image must be named "backgrounddefault". Third, the image size must be less than kb. To ensure that these three requirements are met, "Win + L" locks the desktop to see the effect.