diff --git a/api/src/Vfs/Sharing.php b/api/src/Vfs/Sharing.php
index df84f3b799..196d789d97 100644
--- a/api/src/Vfs/Sharing.php
+++ b/api/src/Vfs/Sharing.php
@@ -169,8 +169,8 @@ class Sharing
 			if (!isset($_SERVER['PHP_AUTH_PW'])) $_SERVER['PHP_AUTH_PW'] = '';
 
 			unset($GLOBALS['egw_info']['flags']['autocreate_session_callback']);
-			if (isset($GLOBALS['egw']->sharing) && $GLOBALS['egw']->session->verify() &&
-				$GLOBALS['egw']->sharing->share['share_token'] === $token)
+			if (isset($GLOBALS['egw']->session) && $GLOBALS['egw']->session->verify()
+				&& isset($GLOBALS['egw']->sharing) && $GLOBALS['egw']->sharing->share['share_token'] === $token)
 			{
 				return $GLOBALS['egw']->session->sessionid;
 			}