title: "virtualbox is not installed" : Error while uninstalling virtual box on Mac
body: <p>I have installed <code>vagrant</code> and <code>virtualbox</code> on my Mac using <code>brew cask</code>. I want to uninstall virtual box. I get the following error when I run the <code>brew cask uninstall virtualbox</code></p>
  
  <pre><code>Error: virtualbox is not installed
  </code></pre>
  
  <p>I can clearly see that virtualbox is installed on my machine and it appears in launcher section. I also see virtualbox, when I run the following command.</p>
  
  <pre><code>$brew cask list
  adium          adobe-reader   consul         google-chrome  iterm2     java6      osxfuse    vagrant    virtualbox     xquartz 
  </code></pre>
  
  <p>Am I missing something here which prevents me to uninstall virtualbox. Any help would be appreciated.</p>