title: AppFileTypes format in Desktop Bridge DesktopAppConverter
body: <p><a href="https://docs.microsoft.com/en-us/windows/uwp/porting/desktop-to-uwp-run-desktop-app-converter#setup-conversion" rel="nofollow noreferrer">The documentation for the DesktopAppConverter</a> shows that <code>-AppFileTypes</code> are to be specified as a comma-delimted list.</p>
  
  <p>To be exact:</p>
  
  <blockquote>
    <p><strong>W_INVALID_FILE_TYPE_ASSOCIATION</strong><br>
    <em>A comma-separated list of file types which the application will be associated with (eg. ".txt, .doc", without the quotes).</em></p>
  </blockquote>
  
  <p>I'm trying to set two extensions (.md and .markdown) but no matter what I try the the converter gives an extension error:</p>
  
  <blockquote>
    <p>WARNING: DesktopAppConverter : warning 'W_INVALID_FILE_TYPE_ASSOCIATION': Rejected invalid application file type association(s): .md,.markdown</p>
  </blockquote>
  
  <p>I've tried:
  *   -AppFileTypes .md,.markdown  (which seems to be what the docs suggest)
  *   -AppFileTypes ".md,.markdown"
  *   -AppFileTypes ".md",".markdown"</p>
  
  <p>None of these combinations work. Any idea on what the right format is?</p>
  
  <p>FWIW a single extension works either quoted or unquoted.</p>