Why doesn't my WCF service hosted by a Windows service work?
[ServiceContract]
public interface IPublishing
{
    [OperationContract(IsOneWay = true)]
    void Publish(Message e, string topicName);
}

[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerCall)]
public class Publishing : IPublishing
{
    public void Publish(Message e, string topicName)
    {
        List<IPublishing> subscribers = Filter.GetSubscribers(topicName);
        if (subscribers == null) return;

        Type type = typeof(IPublishing);
        MethodInfo publishMethodInfo = type.GetMethod("Publish");

        foreach (IPublishing subscriber in subscribers)
        {
            try
            {
                publishMethodInfo.Invoke(subscriber, new object[] { e, topicName });
            }
            catch
            {
            }
        }
    }
}

[ServiceContract(CallbackContract = typeof(IPublishing))]
public interface ISubscription
{
    [OperationContract]
    void Subscribe(string topicName);

    [OperationContract]
    void UnSubscribe(string topicName);
}

[ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)]
public class Subscription : ISubscription
{
    public void Subscribe(string topicName)
    {
        IPublishing subscriber = OperationContext.Current.GetCallbackChannel<IPublishing>();
        Filter.AddSubscriber(topicName, subscriber);
    }

    public void UnSubscribe(string topicName)
    {
        IPublishing subscriber = OperationContext.Current.GetCallbackChannel<IPublishing>();
        Filter.RemoveSubscriber(topicName, subscriber);
    }
}

class Filter
{
    static Dictionary<string, List<IPublishing>> _subscribersList = new Dictionary<string, List<IPublishing>>();

    static public Dictionary<string, List<IPublishing>> SubscribersList
    {
        get {
            lock (typeof(Filter))
            {
                return _subscribersList;
            }
        }
    }

    static public List<IPublishing> GetSubscribers(String topicName)
    {
        lock (typeof(Filter))
        {
            if (SubscribersList.ContainsKey(topicName))
            {
                return SubscribersList[topicName];
            }
            else
                return null;
        }
    }

    static public void AddSubscriber(String topicName, IPublishing subscriberCallbackReference)
    {
        lock (typeof(Filter))
        {
            if (SubscribersList.ContainsKey(topicName))
            {
                if (!SubscribersList[topicName].Contains(subscriberCallbackReference))
                {
                    SubscribersList[topicName].Add(subscriberCallbackReference);
                }
            }
            else
            {
                List<IPublishing> newSubscribersList = new List<IPublishing>();
                newSubscribersList.Add(subscriberCallbackReference);
                SubscribersList.Add(topicName, newSubscribersList);
            }
        }
    }

    static public void RemoveSubscriber(String topicName, IPublishing subscriberCallbackReference)
    {
        lock (typeof(Filter))
        {
            if (SubscribersList.ContainsKey(topicName))
            {
                if (SubscribersList[topicName].Contains(subscriberCallbackReference))
                {
                    SubscribersList[topicName].Remove(subscriberCallbackReference);
                }
            }
        }
    }
}

[DataContract]
public class Message
{
    private string _topicName;
    private string _eventData;

    [DataMember]
    public string TopicName { get { return _topicName; } set { _topicName = value; } }

    [DataMember]
    public string EventData { get { return _eventData; } set { _eventData = value; } }
}

public partial class PublisherForm : Form
{
    IPublishing _proxy;
    int _eventCounter;

    public PublisherForm()
    {
        InitializeComponent();
        CreateProxy();
        _eventCounter = 0;
        txtTopicName.Text = "Bangladesh";
        txtEventData.Text = "Cox's Bazar sea Beach of Bangladesh is really an exceptional creation of God";
    }

    private void CreateProxy()
    {
        string endpointAddressInString = ConfigurationManager.AppSettings["EndpointAddress"];
        EndpointAddress endpointAddress = new EndpointAddress(endpointAddressInString);
        //WSDualHttpBinding wsDualHttpBinding = new WSDualHttpBinding();
        //_proxy = ChannelFactory<IPublishing>.CreateChannel(wsDualHttpBinding, endpointAddress);
        NetTcpBinding netTcpBinding = new NetTcpBinding();
        _proxy = ChannelFactory<IPublishing>.CreateChannel(netTcpBinding, endpointAddress);
    }

    void SendEvent(object sender, EventArgs e)
    {
        try
        {
            string topicName = txtTopicName.Text.Trim();
            if (string.IsNullOrEmpty(topicName))
            {
                MessageBox.Show("Please Enter a Topic Name");
                return;
            }

            Server.Message alertData = PrepareEvent();
            _proxy.Publish(alertData, topicName);
            _eventCounter += 1;
            txtEventCount.Text = _eventCounter.ToString();
        }
        catch { }
    }

    private Server.Message PrepareEvent()
    {
        Server.Message e = new Server.Message();
        e.TopicName = txtTopicName.Text;
        e.EventData = txtEventData.Text;
        return e;
    }

    void SendAutoEvent(object sernder, EventArgs e)
    {
        string topicName = txtTopicName.Text.Trim();
        if (string.IsNullOrEmpty(topicName))
        {
            MessageBox.Show("Please Enter a Topic Name");
            return;
        }
        txtTopicName.ReadOnly = true;
        int interval = 1000;
        tmrEvent.Interval = interval;
        tmrEvent.Enabled = true;
    }

    void StopAutoEvent(object sender, EventArgs e)
    {
        if (tmrEvent.Enabled)
            tmrEvent.Enabled = false;
        txtTopicName.ReadOnly = false;
    }

    void OnResetCounter(object sender, EventArgs e)
    {
        _eventCounter = 0;
        txtEventCount.Text = _eventCounter.ToString();
    }

    private void tmrEvent_Tick(object sender, EventArgs e)
    {
        SendEvent(sender, e);
    }
}

public partial class Subscriber : Form, IPublishing
 {
    ISubscription _proxy;
    static int _eventCount;
    string _endpoint = string.Empty;

    public Subscriber()
    {
        InitializeComponent();
        _endpoint = ConfigurationManager.AppSettings["EndpointAddress"];
        MakeProxy(_endpoint, this);
        _eventCount = 0;
        txtTopicName.Text = "Bangladesh";
    }


    public void MakeProxy(string EndpoindAddress, object callbackinstance)
    {
        NetTcpBinding netTcpbinding = new NetTcpBinding(SecurityMode.None);
        EndpointAddress endpointAddress = new EndpointAddress(EndpoindAddress);
        InstanceContext context = new InstanceContext(callbackinstance);

        DuplexChannelFactory<ISubscription> channelFactory = new DuplexChannelFactory<ISubscription>(new InstanceContext(this), netTcpbinding, endpointAddress);
        _proxy  = channelFactory.CreateChannel();
    }

    void OnSubscribe(object sender, EventArgs e)
    {
        try
        {
            string topicName = txtTopicName.Text.Trim();
            if (string.IsNullOrEmpty(topicName))
            {
                MessageBox.Show("Please Enter a Topic Name");
                return;
            }
            _proxy.Subscribe(topicName);
            ((Button)sender).Visible = false;
            button2.Visible = true;
        }
        catch
        {

        }
    }

    void OnUnSubscribe(object sender, EventArgs e)
    {
        string topicName = txtTopicName.Text.Trim();
        if (string.IsNullOrEmpty(topicName))
        {
            MessageBox.Show("Please Enter a Topic Name");
            return;
        }
        ((Button)sender).Visible = false;
        button1.Visible = true;
        _proxy.UnSubscribe(topicName);
    }

    private void btnClearAstaListView_Click(object sender, EventArgs e)
    {
        lstEvents.Items.Clear();
    }

    public void Publish(Server.Message e, String topicName)
    {
        if (e != null)
        {
            int itemNum = (lstEvents.Items.Count < 1) ? 0 : lstEvents.Items.Count;
            lstEvents.Items.Add(itemNum.ToString());
            lstEvents.Items[itemNum].SubItems.AddRange(new string[] { e.TopicName.ToString(), e.EventData });
            _eventCount += 1;
            txtAstaEventCount.Text = _eventCount.ToString();
        }
    }
}

ServiceHost _publishServiceHost = null;
    ServiceHost _subscribeServiceHost = null;

    public Server()
    {
        InitializeComponent();
        try
        {
            HostPublishService();
            HostSubscriptionService();
        }
        catch
        {
        }
    }

    private void HostSubscriptionService()
    {
        _subscribeServiceHost = new ServiceHost(typeof(Subscription));
        //WSDualHttpBinding httpBinding = new WSDualHttpBinding();
        NetTcpBinding tcpBinding = new NetTcpBinding(SecurityMode.None);

        _subscribeServiceHost.AddServiceEndpoint(typeof(ISubscription), tcpBinding,
                            "net.tcp://localhost:7002/Sub");
        _subscribeServiceHost.Open();
    }

    private void HostPublishService()
    {
        _publishServiceHost = new ServiceHost(typeof(Publishing));
        NetTcpBinding tcpBindingpublish = new NetTcpBinding();

        _publishServiceHost.AddServiceEndpoint(typeof(IPublishing), tcpBindingpublish,
                                "net.tcp://localhost:7001/Pub");
        _publishServiceHost.Open();
    }
}

partial class PubSubServices : ServiceBase
{
    ServiceHost _publishServiceHost = null;
    ServiceHost _subscribeServiceHost = null;

    public PubSubServices()
    {
        InitializeComponent();
    }

    protected override void OnStart(string[] args)
    {
        HostSubscriptionService();
        HostPublishService();
        // TODO: Add code here to start your service.
    }

    protected override void OnStop()
    {
        // TODO: Add code here to perform any tear-down necessary to stop your service.
    }

    private void HostSubscriptionService()
    {
        _subscribeServiceHost = new ServiceHost(typeof(Subscription));
        //WSDualHttpBinding httpBinding = new WSDualHttpBinding();
        NetTcpBinding tcpBinding = new NetTcpBinding(SecurityMode.None);

        _subscribeServiceHost.AddServiceEndpoint(typeof(ISubscription), tcpBinding,
                            "net.tcp://localhost:7002/Sub");
        _subscribeServiceHost.Open();
    }

    private void HostPublishService()
    {
        _publishServiceHost = new ServiceHost(typeof(Publishing));
        NetTcpBinding tcpBindingpublish = new NetTcpBinding();

        _publishServiceHost.AddServiceEndpoint(typeof(IPublishing), tcpBindingpublish,
                                "net.tcp://localhost:7001/Pub");
        _publishServiceHost.Open();
    }
}

public void Publish(Server.Message e, String topicName)
    {
        if (e != null)
        {
            int itemNum = (lstEvents.Items.Count < 1) ? 0 : lstEvents.Items.Count;
            lstEvents.Items.Add(itemNum.ToString());
            lstEvents.Items[itemNum].SubItems.AddRange(new string[] { e.TopicName.ToString(), e.EventData });
            _eventCount += 1;
            txtAstaEventCount.Text = _eventCount.ToString();

        }
    }