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no connection could be made because the target machine actively refused it
i need to know what is the problem and how can solve
i try to ping that (this access point take ip through tcp/ ip module )and that replay no problem

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Net.Sockets;
using System.Threading;
using System.Runtime.Remoting.Channels;
namespace simple_tcpclient
    public partial class Form1 : Form
        public Form1()
        private void Form1_Load(object sender, EventArgs e)
            Connect("", "1");
          public static void Connect(String server, String message) 
    // Create a TcpClient. 
    // Note, for this client to work you need to have a TcpServer  
    // connected to the same address as specified by the server, port 
    // combination.
    int port = 1024;
    TcpClient client = new TcpClient(server, port);
    // Translate the passed message into ASCII and store it as a Byte array.
    Byte[] data = System.Text.Encoding.ASCII.GetBytes(message);         
    // Get a client stream for reading and writing. 
   //  Stream stream = client.GetStream();
    NetworkStream stream = client.GetStream();
    // Send the message to the connected TcpServer. 
    stream.Write(data, 0, data.Length);
    System.Windows.Forms.MessageBox.Show("Sent: {0}" + message); ;         
    // Receive the TcpServer.response. 
    // Buffer to store the response bytes.
    data = new Byte[256];
    // String to store the response ASCII representation.
    String responseData = String.Empty;
    // Read the first batch of the TcpServer response bytes.
    Int32 bytes = stream.Read(data, 0, data.Length);
    responseData = System.Text.Encoding.ASCII.GetString(data, 0, bytes);
    System.Windows.Forms.MessageBox.Show("recieved: {0}"+ responseData); 
    // Close everything.
   // stream.Close();         
   // client.Close();         
  catch (ArgumentNullException e) 
      System.Windows.Forms.MessageBox.Show("ArgumentNullException: {0}"+ e);
  catch (SocketException e) 
      System.Windows.Forms.MessageBox.Show("SocketException: {0}"+ e);
  System.Windows.Forms.MessageBox.Show("\n Press Enter to continue...");








Posted 6-Mar-13 20:40pm

1 solution

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Solution 1

Your code connects to port 1024 of the host (

int port = 1024;
TcpClient client = new TcpClient(server, port);

According to exception - no service listens on this port at this host.

You can check if this port is open using telnet program

telnet 1024

To resolve - ensure, that on host some application listens to this port.
ameleed 7-Mar-13 4:18am
Vyacheslav Voronenko
you mean insert that (telnet 1024)to my code . i already insert it to the code but it isn't identified how can i identify it ?
i am searching in this is exception and i find that may because of the firewall of my host ( block the call. so do you think the problem is in hardware or in my application
Vyacheslav Voronenko 7-Mar-13 6:37am
What is the result of telnet 1024 command?

Connecting To not open connection to the host, on port 1024: Connect failed

Than problem is not in your application.
ameleed 9-Mar-13 7:17am
yes i use this is to make telnet and service is not running what is the problem ?
Vyacheslav Voronenko 10-Mar-13 3:54am
You do not need any C# here - it just allows you to simply check if smth listens to remote port or not.

From the command prompt.
ameleed 10-Mar-13 8:26am
yes i made that from command prompt
and the result of telnet 1024
is could not open connection to the host on port connected failed
what can i do in this problem
may be firewall in my pc or firewall in the wireless access point or may be need to open port 1024
can you help me to find the solution
Vyacheslav Voronenko 10-Mar-13 10:25am
You have to solve this problem at your box - run something that you were expecting to contact at this port. (What is it?)
ameleed 10-Mar-13 12:35pm
the box is this is device
Vyacheslav Voronenko 10-Mar-13 13:06pm
Looking on docs - are you sure device is correctly configured (in terms of address) and is located in the same network range as your computer? Is standalone test with elTest tool passed?
ameleed 13-Mar-13 3:26am
thanks i will test the e1test
ameleed 15-Mar-13 6:55am
wow yes Vyacheslav Voronenko as you said
now i can connect and my application is run and problem and no error
thanks for you
i am very pleased to help me
Vyacheslav Voronenko 15-Mar-13 6:56am
No problem at all :) Cheers!
ameleed 15-Mar-13 7:21am
yes :)

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

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