title: how to resolve issue where Vagrant fails to bring up VirtualBox on OS X El Capitan?
body: <p>I am getting the following issue trying to start a VM using vagrant &amp; VirtualBox on my MacBook Air (13-inch, Early 2015) running OS X 10.11.6.  I have tried VirtualBox version 5.0.26, 5.1.0 and 5.1.2.  I have searched around and tried all the suggestions I could find. what do I need to do to fix this issue?</p>
  
  <pre><code>There was an error while executing `VBoxManage`, a CLI used by Vagrant
  for controlling VirtualBox. The command and stderr is shown below.
  
  Command: ["startvm", "23e70124-39c9-46ea-a45d-cf34c0e8a251", "--type", "headless"]
  
  Stderr: VBoxManage: error: The VM session was aborted
  VBoxManage: error: Details: code NS_ERROR_FAILURE (0x80004005), component SessionMachine, interface ISession
  </code></pre>