Changing Desktop Solid Color Via Registry
Solution 1:
HKCU\Control Panel\Colors\Background
It's a string with a space between the numbers for red/green/blue, for instance for straight blue: "0 0 255"
Solution 2:
the command line "reg add" works well. You can also import this registry:
Windows Registry Editor Version 5.00
; remove picture wallpaper
[HKEY_CURRENT_USER\Control Panel\Desktop]
"WallPaper"=""
; set RGB = black
[HKEY_CURRENT_USER\Control Panel\Colors]
"Background"="0 0 0"
Solution 3:
You can change the desktop background for a user in the registry.
First remove the wallpaper, if there is one:
reg add "HKEY_CURRENT_USER\Control Panel\Desktop" /v WallPaper /t REG_SZ /d " " /f
Then set you color. The values are in RGB so for example "255 0 0"
would be red.
reg add "HKEY_CURRENT_USER\Control Panel\Colors" /v Background /t REG_SZ /d "0 66 117" /f
Solution 4:
The changes on the registry are not applied immediately.
A better alternative would be to use the windows function SetSysColors in C++.
See this answer: https://stackoverflow.com/a/19849675/3844137