Why does Valve.VR not work when using visual studio?

[squeakyonvr]

so look I have an image here that shows me using Valve.VR just how I was told to on many searches I even have the newest version of visual studio with C# downloaded same with unity and all the other editing things you would need to create what I'm making but still it doesn't work still there are many codes that do not work without them, I've even asked some of the people who created these tutorials and they said that they don't know why its not working for me and others if anyone knows how to fix it tell me and if its just a unity bug then so be it