diff --git a/lib/tfw/networking/server/event_handler_connector.py b/lib/tfw/networking/server/event_handler_connector.py
index a40425f..1e7ca69 100644
--- a/lib/tfw/networking/server/event_handler_connector.py
+++ b/lib/tfw/networking/server/event_handler_connector.py
@@ -35,6 +35,5 @@ class EventHandlerConnector(EventHandlerDownlinkConnector, EventHandlerUplinkCon
         self._zmq_pull_stream.on_recv(callback)
 
     def send_message(self, message: dict, key: str = None):
-        if not key:
-            key = message['key']
+        if not key: key = message.get('key', '')
         self._zmq_pub_socket.send_multipart(serialize_all(key, message))