While working on applying Windows Wallpapers with Group Policy’s I noticed a lot of computers got this annoying block screen. No matter what I did the screen just stayed black. No amount of theme changing, new backgrounds or any other trick worked.
So what worked
Windows saves the theme settings in a file called TranscodedWallpaper.
This file can normally be located by opening a Run command and pasting the below folder path in it and opening it up.
Simply browse to the location and delete all the files within.
Ease of Access
Lastly, open Setting and browse to Ease of access on the left choose Display and look for the option Show Desktop Background Image.
This option must then be turned off and back on. It basically recreates the TrancodedWallpaper file.
On the machines, I tested the Wallpaper immediately appeared again. In some instances, a simple reboot would do.