diff --git a/Remote/External.hs b/Remote/External.hs
index 2507196417..3dad99022c 100644
--- a/Remote/External.hs
+++ b/Remote/External.hs
@@ -222,6 +222,7 @@ sendMessage lck external m =
 		liftIO $ do
 			protocolDebug external True line
 			hPutStrLn h line
+			hFlush h
   where
 	line = unwords $ formatMessage m