title: System.Environment.OSVersion returns wrong version
body: <p>Using windows 10, upgraded from windows 8 => 8.1 => 10 When I use this code.</p>
  
  <pre><code>OperatingSystem os = System.Environment.OSVersion;
  </code></pre>
  
  <p>The os.Version =    {6.2.9200.0}    System.Version</p>
  
  <p>I read this was because of the version it was <a href="https://msdn.microsoft.com/en-us/library/windows/desktop/ms724832(v=vs.85).aspx" rel="noreferrer" title="manifested for">manifested for</a> but I do not understand what that means.</p>
  
  <p>I want the correct OS version because I am logging a user agent string on a web service, and want to correctly identify the windows version for support.  what is the easiest way to get that to correctly report the correct version?</p>