After searching a lot on internet when i could not get a solution I am here.
I have a requirement in my project which supports multiple languages. When I am switching to a specific language It works fine if the language is already there in system language preferences if not it shows an error. To resolve error I had to go manually to the below location and then add language.
Control Panel\All Control Panel Items\Language >> Add a Language
And everything works as expected. Now This is what I want to do programmatically i.e. In code somehow I could add a language to system language preference list.
(c# - preferred language).
Hope you guys will drag me out of this hell.