C# Socket Exception : an attempt was made to access a socket in a way forbidden by its access permissions

This is my code what I am using. This is the code I got from the internet, They said it is working fine. The comments for this also good but I don't understand why it is not working for me. And one more thing I am using this application as user mode not in a administrator mode.

private void btnStart_Click(object sender, EventArgs e)
    {
        if (cmbInterfaces.Text == "")
        {
            MessageBox.Show("Select an Interface to capture the packets.", "MJsniffer", 
                MessageBoxButtons.OK, MessageBoxIcon.Error);
            return;
        }
        try
        {
            if (!bContinueCapturing)        
            {
                //Start capturing the packets...

                btnStart.Text = "&Stop";

                bContinueCapturing = true;

                //For sniffing the socket to capture the packets has to be a raw socket, with the
                //address family being of type internetwork, and protocol being IP
                Console.WriteLine("1");
                mainSocket = new Socket(AddressFamily.InterNetwork,
                    SocketType.Raw, ProtocolType.IP);
                Console.WriteLine("2");
                //Bind the socket to the selected IP address
                mainSocket.Bind(new IPEndPoint(IPAddress.Parse(cmbInterfaces.Text), 0));
                Console.WriteLine("3");
                //Set the socket  options
                mainSocket.SetSocketOption(SocketOptionLevel.IP,            //Applies only to IP packets
                                           SocketOptionName.HeaderIncluded, //Set the include the header
                                           true);                           //option to true
                Console.WriteLine("4");
                byte[] byTrue = new byte[4] {1, 0, 0, 0};
                byte[] byOut = new byte[4]{1, 0, 0, 0}; //Capture outgoing packets

                //Socket.IOControl is analogous to the WSAIoctl method of Winsock 2
                mainSocket.IOControl(IOControlCode.ReceiveAll,              //Equivalent to SIO_RCVALL constant
                                                                            //of Winsock 2
                                     byTrue,                                    
                                     byOut);

                //Start receiving the packets asynchronously
                mainSocket.BeginReceive(byteData, 0, byteData.Length, SocketFlags.None,
                    new AsyncCallback(OnReceive), null);
            }
            else
            {
                btnStart.Text = "&Start";
                bContinueCapturing = false;
                //To stop capturing the packets close the socket
                mainSocket.Close ();
            }
        }
        catch (SocketException ex)
        {
            Console.WriteLine("5");
            MessageBox.Show(ex.Message, "MJsniffer", MessageBoxButtons.OK, MessageBoxIcon.Error);
        }
        catch (Exception ex)
        {
            Console.WriteLine("6");
            MessageBox.Show(ex.Message, "MJsniffer", MessageBoxButtons.OK, MessageBoxIcon.Error);
        }
    }