title: The default controller for extension and plugin can not be determined
body: <p>Good afternoon, dear friends! All, I give up. Tried well, all that was already possible. TYPO3 7.6.16</p>
  
  <p>ext_tables.php:</p>
  
  <pre><code>&lt;?php
  
  if (!defined('TYPO3_MODE')) die ('Access denied.');
  
  \TYPO3\CMS\Extbase\Utility\ExtensionUtility::registerPlugin(
      'MyVendor.' . $_EXTKEY,
      'Pi1',
      'The inventory list'
  );
  </code></pre>
  
  <p>ext_localconf.php:</p>
  
  <pre><code>&lt;?php
  if (!defined('TYPO3_MODE')) die ('Access denied.');
  
  \TYPO3\CMS\Extbase\Utility\ExtensionUtility::configurePlugin(
      'MyVendor.' . $_EXTKEY,
      'Pi1',
      Array ('Comment' =&gt; 'list'),
      Array ('Comment' =&gt; 'list')
  );
  </code></pre>
  
  <p>And constantly the same mistake
  The default controller for extension "Fecomments" and plugin "Pi1" can not be determined</p>
  
  <p>I read topics with same error but nothing help me.</p>
  
  <p>I already climbed into the kernel, found out that $configuration ['controllerConfiguration'] is an empty array, I do not know why data does not arrive there. Comrades, help me out, I do not know what to do, honestly! )</p>