diff --git a/src/gajim.py b/src/gajim.py
index 2855f741e..66caa9a1c 100755
--- a/src/gajim.py
+++ b/src/gajim.py
@@ -513,7 +513,11 @@ class Interface:
 		ctrl = self.msg_win_mgr.get_control(fjid, account)
 		if ctrl:
 			chat_control = ctrl
-		elif not highest_contact or resource != highest_contact.resource:
+		elif not highest_contact or not highest_contact.resource:
+			# unknow contact or offline message
+			chat_control = None
+			jid_of_control = jid
+		elif resource != highest_contact.resource:
 			chat_control = None
 			jid_of_control = fjid
 		# Handle chat states