title: Value cannot be null. Parameter name: pUnk
body: <p>I have upgraded my visual studio to visual studio 2019 and now sometime with few 
  files while trying to check in code to TFS its giving me error: </p>
  
  <blockquote>
    <p>Value cannot
    be null. Parameter name: pUnk</p>
  </blockquote>
  
  <p>I tried even to delete whole source code and downloaded it again but no success.</p>