title: I added a callback interface method to my existing WCF service, but updating my service reference I don't see it
body: <p>I recently added a ping method to my service which calls a pong method on the callback channel:</p>
  
  <pre><code>public partial class myService
  {
      public void Ping()
      {
          OperationContext.Current.GetCallbackChannel&lt;IKeepAliveEvents&gt;().Pong();
      }
  }
  </code></pre>
  
  <p>I also added in the pong method to the callback interface:</p>
  
  <pre><code>namespace myService
  {
      [ServiceContract]
      public interface IKeepAliveEvents
      {
          [OperationContract(IsOneWay = true)]
          void Pong();
      }
  }
  </code></pre>
  
  <p>Which is inherited in my WCF service's main interface definition:</p>
  
  <pre><code>[ServiceContract]
  public interface IMyServiceEvents : IEvents1, IEvents2, ..., IEvents9, IKeepAliveEvents
  {
      [OperationContract(IsOneWay = true)]
      void TestEvent(string s);
  }
  </code></pre>
  
  <p>And then used as follows:</p>
  
  <pre><code>[ServiceContract(CallbackContract=typeof(IMyServiceEvents)]
  public interface IMyService : ISomething1, ISomething2, ..., ISomething13
  {
      ...
  }
  
  [ServiceBehavior(InstanceContextMode = InstanceContextMode.Single, ConcurrencyMode = ConcurrencyMode.Multiple, MaxItemsInObjectGraph = 2147483647)]
  public partial class myService : IMyService, IDisposable, IServiceBehavior, IErrorHandler {
      ...
  }
  </code></pre>
  
  <p>The problem is...when my WCF service is running, it won't let me implement the pong method in my client application from the interface definition because it doesn't seem to exist each time I try to update the service...and for sure I am updating the correct service at the correct URL, and for sure I am using the latest build's code as I have been able to attach the debugger to my service and put a break-point into the Ping method where it calls Pong. Even more strange is that the Ping method does exist for my client to consume it, but the Pong method does not seem to want to show up here on the client:</p>
  
  <pre><code>public partial class myClientEndpoint : myServiceCallback {
      // I would expect Pong to be implementable here.
  }
  </code></pre>
  
  <p>What could the problem be?</p>