Basic WebSocketSharp client connection in C#

Question

How do I get this to work:

using (var ws = new WebSocket("wss://echo.websocket.org"))
{
    ws.OnMessage += (sender, e) =>
      Console.WriteLine("RESPONSE: " + e.Data);

    ws.Connect();
    ws.Send("TEST SEND");
    Console.ReadKey(true);
}

The error is:

Authentication failed because the remote party has closed the transport stream.

Answer 1

Seems to work if I use:

using (var ws = new WebSocket("ws://echo.websocket.org"))