diff --git a/index.php b/index.php
index 16597fa62e..3a2067471e 100644
--- a/index.php
+++ b/index.php
@@ -36,10 +36,6 @@ $a->backend = false;
 require_once "include/dba.php";
 
 if (!$a->mode == App::MODE_INSTALL) {
-	if (!dba::connected()) {
-		System::unavailable();
-	}
-
 	/**
 	 * Load configs from db. Overwrite configs from config/local.ini.php
 	 */
diff --git a/mod/admin.php b/mod/admin.php
index b308a2049b..d431fac2a2 100644
--- a/mod/admin.php
+++ b/mod/admin.php
@@ -845,6 +845,12 @@ function admin_page_summary(App $a)
 		$warningtext[] = L10n::t('The last worker execution was on %s UTC. This is older than one hour. Please check your crontab settings.', $last_worker_call);
 	}
 
+	// Legacy config file warning
+	if (file_exists('.htconfig.php')) {
+		$showwarning = true;
+		$warningtext[] = L10n::t('Friencia\'s configuration now is stored in config/local.ini.php, please copy config/local-sample.ini.php and move your config from <code>.htconfig.php</code>.');
+	}
+
 	$r = q("SELECT `page-flags`, COUNT(`uid`) AS `count` FROM `user` GROUP BY `page-flags`");
 	$accounts = [
 		[L10n::t('Normal Account'), 0],
diff --git a/src/App.php b/src/App.php
index 17cfd3eefc..d35b497c2a 100644
--- a/src/App.php
+++ b/src/App.php
@@ -151,6 +151,12 @@ class App
 
 		$this->determineMode();
 
+		if ($this->mode === self::MODE_NORMAL) {
+			Core\Addon::loadHooks();
+
+			$this->loadAddonConfig();
+		}
+
 		$this->loadDefaultTimezone();
 
 		$this->performance['start'] = microtime(true);
@@ -295,6 +301,12 @@ class App
 		$this->register_template_engine('Friendica\Render\FriendicaSmartyEngine');
 	}
 
+	/**
+	 * Load the configuration files
+	 *
+	 * First loads the default value for all the configuration keys, then the legacy configuration files, then the
+	 * expected local.ini.php
+	 */
 	private function loadConfigFiles()
 	{
 		$this->loadConfigFile($this->basepath . DIRECTORY_SEPARATOR . 'config' . DIRECTORY_SEPARATOR . 'defaults.ini.php');
@@ -328,6 +340,23 @@ class App
 		}
 	}
 
+	/**
+	 * Tries to load the specified configuration file into the App->config array.
+	 * Overwrites previously set values.
+	 *
+	 * The config format is INI and the template for configuration files is the following:
+	 *
+	 * <?php return <<<INI
+	 *
+	 * [section]
+	 * key = value
+	 *
+	 * INI;
+	 * // Keep this line
+	 *
+	 * @param type $filepath
+	 * @throws Exception
+	 */
 	public function loadConfigFile($filepath)
 	{
 		if (!file_exists($filepath)) {
@@ -349,6 +378,12 @@ class App
 		}
 	}
 
+	/**
+	 * Loads addons configuration files
+	 *
+	 * First loads all activated addons default configuration throught the load_config hook, then load the local.ini.php
+	 * again to overwrite potential local addon configuration.
+	 */
 	private function loadAddonConfig()
 	{
 		// Loads addons default config
@@ -360,6 +395,13 @@ class App
 		}
 	}
 
+	/**
+	 * Loads the default timezone
+	 *
+	 * Include support for legacy $default_timezone
+	 *
+	 * @global string $default_timezone
+	 */
 	private function loadDefaultTimezone()
 	{
 		if ($this->getConfigValue('system', 'default_timezone')) {
@@ -375,8 +417,7 @@ class App
 	}
 
 	/**
-	 * Figure out if we are running at the top of a domain
-	 * or in a sub-directory and adjust accordingly
+	 * Figure out if we are running at the top of a domain or in a sub-directory and adjust accordingly
 	 */
 	private function determineUrlPath()
 	{
@@ -396,16 +437,31 @@ class App
 		}
 	}
 
+	/**
+	 * Sets the App mode
+	 *
+	 * - App::MODE_INSTALL    : Either the database connection can't be established or the config table doesn't exist
+	 * - App::MODE_MAINTENANCE: The maintenance mode has been set
+	 * - App::MODE_NORMAL     : Normal run with all features enabled
+	 *
+	 * @return type
+	 */
 	private function determineMode()
 	{
 		$this->mode = App::MODE_INSTALL;
 
-		// Missing DB connection
-		if (!\dba::connected()) {
+		// Missing local config files: MODE_INSTALL
+		if (!file_exists($this->basepath . DIRECTORY_SEPARATOR . 'config' . DIRECTORY_SEPARATOR . 'local.ini.php')
+			&& !file_exists($this->basepath . DIRECTORY_SEPARATOR . '.htconfig.php')) {
 			return;
 		}
 
-		// Working DB connection, missing tables
+		// Missing DB connection: ERROR
+		if (!\dba::connected()) {
+			System::unavailable();
+		}
+
+		// Working DB connection, missing tables: MODE_INSTALL
 		if (\dba::fetch_first("SHOW TABLES LIKE 'config'") === false) {
 			return;
 		}