Search notes:

Registry: HKEY_CURRENT_USER\Control Panel\International\User Profile

Languages

The value is a list that is new line separated, such as
en-CH
en-US
de-CH
en-GB
Each of these values seem to correspond to an equally named subkey.
This list seems also to be returned by the PowerShell cmdlet get-WinUserLanguageList.
TODO: How is it related to HKEY_CURRENT_USER\Keyboard Layout\Preload

Index