title: Fatal error: Call to undefined function wp_register_plugin_realpath()
body: <p>I'm having an issue on an old site. This happened at random, and did not follow an upgrae or edit. I've followed the steps outlined in previous questions, including : </p>
  
  <ol>
  <li>Renaming the plugins and adding them back in one by one to see if it fixes the issue.</li>
  <li>Uploading a new plugins.php file from Wordpress' current build</li>
  <li>Uploading a new settings.php file from Wordpress' current build</li>
  </ol>
  
  <p>None of these things have fixed the issue...I only get more warnings. Any other ideas? </p>
  
  <p><a href="http://hoosierpma.com/" rel="nofollow">http://hoosierpma.com/</a></p>