title: "Controller does not exist. Reflection failed." TYPO3
body: <p>I am working on my own extension in TYPO3 (v 9.5.12) and when I click on my extension via Admin Tools, an error message pops up:</p>
  
  <p><a href="https://i.stack.imgur.com/0KxNp.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/0KxNp.png" alt="Error Message"></a></p>
  
  <p>The log reads following error message:</p>
  
  <pre><code>Core: Exception handler (WEB): Uncaught TYPO3 Exception: #1278450972: 
  Class Secsign\Secsign\Controller\SecsignController does not exist. 
  Reflection failed.
  | TYPO3\CMS\Extbase\Reflection\Exception\UnknownClassException thrown in file 
  C:\xampp\htdocs\Typo9\public\typo3\sysext\extbase\Classes\Reflection\ReflectionService.php 
  in line 363. Requested URL: 
  http://localhost/Typo9/public/typo3/index.php?route=%%2Ftools%%2FSecsignSecsignbe%%2F&amp;token=--AnonymizedToken--
  </code></pre>
  
  <p>My composer.json file looks like this.</p>
  
  <pre><code>{
      "name": "secsign/secsign",
      "type": "typo3-cms-extension",
      "description": "This extension allows users to authenticate using their smart phone running the SecSign App.",
      "authors": [
          {
              "name": "SecSign Technologies Inc.",
              "role": "Developer"
          }
      ],
      "require": {
          "typo3/cms-core": "^9.5"
      },
      "autoload": {
          "psr-4": {
              "Secsign\\Secsign\\": "Classes/"
          }
      },
      "autoload-dev": {
          "psr-4": {
              "Secsign\\Secsign\\Tests\\": "Tests/"
          }
      }
  }
  </code></pre>
  
  <p>I do not understand the problem here. How can I get this to work?</p>