diff --git a/lib/private/legacy/app.php b/lib/private/legacy/app.php
index 33b18c0c6a..c2ff9a5be3 100644
--- a/lib/private/legacy/app.php
+++ b/lib/private/legacy/app.php
@@ -381,6 +381,8 @@ class OC_App {
 			// check for required dependencies
 			$info = self::getAppInfo($appId);
 			self::checkAppDependencies($config, $l, $info);
+			$appPath = self::getAppPath($appId);
+			self::registerAutoloading($appId, $appPath);
 			$installer->installApp($appId);
 		}