title: Windows Process Activation Service (WAS) encountered a failure when it started a worker process to serve the application pool
body: <p>IIS 7 Application Pool stops when browsing to <a href="http://localhost/" rel="noreferrer">http://localhost/</a></p>
  
  <p>In Event Viewer -> System Log I see:</p>
  
  <blockquote>
    <p>Application pool ASP.NET v4.0 has been disabled. Windows Process
    Activation Service (WAS) encountered a failure when it started a
    worker process to serve the application pool.</p>
  </blockquote>
  
  <p>Are there other troubleshooting steps I can take to see a more detailed messages of why this is happening? </p>