diff --git a/src/dialogs.py b/src/dialogs.py
index 2fff8c743..f08e515f7 100644
--- a/src/dialogs.py
+++ b/src/dialogs.py
@@ -1471,7 +1471,7 @@ class WarningDialog(HigDialog):
         HigDialog.__init__( self, None,
                                                 gtk.MESSAGE_WARNING, gtk.BUTTONS_OK, pritext, sectext)
         self.set_modal(False)
-        if hasattr(gajim.interface, 'roster'):
+        if hasattr(gajim.interface, 'roster') and gajim.interface.roster:
             self.set_transient_for(gajim.interface.roster.window)
         self.popup()