title: Getting error 500 when trying to obtain access token from authorization code
body: <p>Before this question gets closed as too specific I quote from the official <a href="https://groups.google.com/forum/#!forum/oauth2-dev">Google OAuth Group</a>:</p>
  
  <blockquote>
    <p>As of March 4, 2013, discussion on this group has move to google-oauth
    tag on Stack Overflow</p>
    
    <p>We support the Google OAuth2 on Stack Overflow. Google engineers
    monitor and answer against the tag google-oauth. You should use this
    tag when asking questions.</p>
  </blockquote>
  
  <p>Starting this morning (2014-07-18) some of my users are getting error 500 Internal Server error with payload <code>{ "error" : "internal_failure" }</code> when trying to obtain an access token using a previously obtained authorization code from Google's token endpoint: <code>https://accounts.google.com/o/oauth2/token</code>.</p>
  
  <p>Hopefully some Google engineer monitoring the <code>google-oauth</code> tag here would be able to provide more insight.</p>