title: .dll file not accessible
body: <p>I am trying to add a dll to my project.
  When I do "add reference" and try to add it, it tells me :</p>
  
  <blockquote>
    <p>"A reference to ... could not be added. please make sure that the file
    in accessible, and that it is a valid assembly or COM component".</p>
  </blockquote>
  
  <p>BTW, I am trying to add g729.dll</p>
  
  <p><strong>How can I add the dll?</strong></p>