title: How to enable “Always use the selected program to open this kind of file” option in the open-with-dialog box
body: <p>How can I enable “Always use the selected program to open this kind of file” option in the <em>Open With dialog</em> box?</p>
  <p>I already checked the following registry entries:</p>
  <pre><code>HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer
  Value of &quot;NoFileAssociate&quot; Set to 0 ( as reccomended on Microsoft site )
  
  HKEY_CLASSES_ROOT\Unknown\shell\openas\command
  Value of &quot;Default&quot; set to
  %SystemRoot%\system32\rundll32.exe %SystemRoot%\system32\shell32.dll,OpenAs_RunDLL %1
  </code></pre>
  <p>What else could cause the “Always use the selected program to open this kind of file” option to be disabled?</p>