System.AggregateException' in mscorlib.dll in SignalR

public class Provider

{

static void Main(string[] args)

{

var connection = new HubConnection("http://192.168.1.88:8044/");

var myHub = connection.CreateHubProxy("LocationHub");

//This line it displaying Exception thrown: 'System.AggregateException' in mscorlib.dll 

connection.Start().Wait();

myHub.On("addMessage", myString =>

{

Console.WriteLine("This is client getting messages from server :{0}", myString);

});

myHub.Invoke("Chatter", System.DateTime.Now.ToString()).Wait();

Console.Read();

}

}

-----------------------

class Program

{

static void Main(string[] args)

{

string url = "http://192.168.1.88:8044/";

using (WebApp.Start(url))

{

Console.WriteLine("Server running on {0}", url);

Console.ReadLine();

IHubContext context = GlobalHost.ConnectionManager.GetHubContext();

for (int i = 0; i < 100; i++)

{

System.Threading.Thread.Sleep(3000);

context.Clients.All.addMessage("Current integer value : " + i.ToString());

}

Console.ReadLine();

}

}

}

[HubName("LocationHub")]

public class LocationHub : Hub

{

public void Send(string platform, string message)

{

Clients.All.messageReceived(platform, message);

}

}

}

public class Startup

{

public void Configuration(IAppBuilder app)

{

app.MapSignalR();

}

}

 

 Error:

 Exception thrown: 'System.AggregateException' in mscorlib.dll 

Inner Exception is:

 {"StatusCode: 404, ReasonPhrase: 'Not Found', Version: 1.1, Content: System.Net.Http.StreamContent, Headers:\r\n{\r\n Cache-Control: private\r\n Date: Tue, 20 Dec 2016 09:09:06 GMT\r\n Server: Microsoft-IIS/10.0\r\n X-Powered-By: ASP.NET\r\n Content-Length: 4938\r\n Content-Type: text/html; charset=utf-8\r\n}"}