diff --git a/websocket-sharp/WebSocket.cs b/websocket-sharp/WebSocket.cs
index 2ba61f95..07289605 100644
--- a/websocket-sharp/WebSocket.cs
+++ b/websocket-sharp/WebSocket.cs
@@ -2480,8 +2480,8 @@ namespace WebSocketSharp
     /// </remarks>
     public void ConnectAsync ()
     {
-      var msg = checkIfAvailable (true, false, true, false, false, true);
-      if (msg != null) {
+      string msg;
+      if (!checkIfAvailable (true, false, true, false, false, true, out msg)) {
         _logger.Error (msg);
         error ("An error has occurred in connecting.", null);