diff --git a/tryton/gui/main.py b/tryton/gui/main.py
index 26a8e42e8e..9d90cfecee 100644
--- a/tryton/gui/main.py
+++ b/tryton/gui/main.py
@@ -928,7 +928,7 @@ class Main(object):
                 prefs = RPCExecute('model', 'res.user', 'get_preferences',
                     False)
             except RPCException:
-                prefs = None
+                prefs = {}
             common.ICONFACTORY.load_icons()
             if prefs and 'language_direction' in prefs:
                 translate.set_language_direction(prefs['language_direction'])