As with the case of Windows 8, its successor Windows 8.1 also lets you customize the background color of the logon screen, the screen that appears right after the lock screen and displays your user account name, picture, and shut down options.
While one can always change the default color of the logon screen by switching to the Start screen, opening Settings charm, and then clicking the Personalize option, when you change the logon screen background, it also changes the Start screen background color.
In other words, Windows uses the same background color that you have set for the Start screen as logon screen background color. That’s is, you can’t set separate colors for your Start screen background and logon screen background. However, if you have configured Windows 8.1 to use desktop background as Start screen background, you’ll be able use separate colors for Start and logon screen without the help of third-party tools.
Users who are using one of the backgrounds that ship with Windows 8.1 as Start screen background and want to have separate colors for Start and logon screen, need to use a third-party tool named Start Screen Color Tuner.
Start Screen Color Tuner is a new tool released by our friend at WinAero to help Windows 8.1 users have separate colors for both Start screen and logon screen. Those of you have upgraded from Windows 8 would know that a similar tool named Sign-in Screen Color Changer is available for the same job. However, according to the developer, the old tool doesn’t work in Windows 8.1 and one needs to use Start Screen Color Tuner for the job.
Using Start Screen Color Tuner is fairly simple. Download Start Screen Color Changer zip file (download link mentioned at the end of this post), extract the contents of the zip file to get two folders titled x86 and x64, depending on the version of Windows 8.1 you’re running run the Start Screen Color Tuner executable located in x86 or x64 folder, click on the color box next to the logon screen color option, select a color from the available colors, click OK button, and finally, click Yes button when you see the UAC prompt to set a new color as logon screen background.
As you can see in the above picture, Start Screen Color Tuner lets you set a color for Start screen background as well.
Options are available to reset the logon screen color to the default and also export the Registry key with the new color so that you can quickly import this file to another Windows 8.1 PC and have the same color as logon background.
Please note that as of writing this article, it’s not possible to set a picture as logon screen background in Windows 8 and Windows 8.1.