WCF Duplex Contract with ASP.NET web application as a client using netTcpBinding

Question

Hello

I've written a WCF service which has a duplex contract and uses netTcpBinding. I've implemented the callback contract in the client side. The client is a ASP.Net web application. I created a new class file in the project and implemented the CallbackContract. From the class i'm passing the value to the page which binds the value to a listbox control.

Issue

I'm able to see that the callback is raised. I'm adding a new item in the listbox. But it is not getting displayed in the page (no postback too). I've set autopostback = true for the listbox.

Other details Service - selfhosting using a console application Client - ASP.Net web app binding - netTcpBinding

Config - Server side

<behaviors>
  <serviceBehaviors>
    <behavior  name="MyBehavior">
      <serviceThrottling maxConcurrentSessions="10000" />
    </behavior>
  </serviceBehaviors>
</behaviors>

<bindings>
  <netTcpBinding>
    <binding name="DuplexBinding" sendTimeout="00:00:51">
      <reliableSession enabled="true" />
      <security mode="None" />
    </binding>
  </netTcpBinding>
</bindings>

Config - Client Side

<system.serviceModel>
  <client>
    <endpoint name=""
              address="net.tcp://localhost:22222/service"
              binding="netTcpBinding"
              bindingConfiguration="DuplexBinding"
              contract="IMain" />
  </client>
  <bindings>
    <netTcpBinding>
      <binding name="DuplexBinding" sendTimeout="00:00:05" >
        <reliableSession enabled="true" />
        <security mode="None" />
      </binding>
    </netTcpBinding>
  </bindings>
</system.serviceModel>

Any ideas?

Thank you

NLV