fix broken link (resolves #83)

Author: malte-christian

troubleshooting/debug-mode.md

@@ -1,7 +1,7 @@
 # Debug Mode
 <p class="uk-article-lead">There are situations where the root cause for an error is not clear and requires extra steps to detect.</p>
 
-By default, Pagekit will hide any PHP errors. In order to show them, the **Debug Mode** must be enabled in _System > Settings_ or it must be set to `true` in the [configuration file](getting-started/configuration-file.md) manually.
+By default, Pagekit will hide any PHP errors. In order to show them, the **Debug Mode** must be enabled in _System > Settings_ or it must be set to `true` in the [configuration file](../getting-started/configuration-file.md) manually.
 
 **Note** If an error happens during the installation, the configuration file will not be generated. In that case, you need to edit the default config file located in `app/installer/config.php`.