title: Class not registered exception when calling a WinRT compontent after migrating to VS2013.4
body: <p>I have a HTML5 application, that contains a .winmd component used for file system operations (sqlite, zip archives and so on).</p>
  
  <p>After I upgraded to 2013.4 this component suddenly stopped working. Javascript still sees all the classes and function, but when I attempt to call any of them I get "WinRT: Class not registered" exception.</p>
  
  <p>Full VS reinstall didn't help. Neither did upgrading to community version. This behavior is reproduced on both desktop (8.1pro) and laptop (win8.1 single language)</p>
  
  <p>I spent 2 days trying to figure out what's wrong and I found that it fails as soon as component includes any asyncronous activity (like await/async or just Task.Delay(100))</p>
  
  <p>So my concern is... What's going on? Where I was wrong and what can I do?</p>
  
  <p>Right now installing 2015 preview. If I roll back to 2013.3 using system restore, project works fine, but VS gets in semi-broken state, and there is no link on a MS website to download previous version.</p>
  
  <p>If what I say doesn't make any sense, i may upload a file with a simpliest possible VS solution to reproduce a problem. But in brief it's as simple as:</p>
  
  <pre><code>namespace NSUtil {
    public sealed class Test{
      public static IAsyncOperation&lt;string&gt; DoSomething () {
        return Task&lt;string&gt;.Run(async () =&gt; {
          await Task.Delay(100);
          return "";
        }).AsAsyncOperation();
      }
    }
  }
  </code></pre>
  
  <p>and as soon as I call <code>NSUtil.Test.doSomething()</code> from javascript, i get <code>WinRTError: Class not registered</code> exception.</p>
  
  <p>So the question is.... What's wrong with me/my pc/my vs installation/microsoft developers?</p>