WCF client works fine IIS express but not with Local IIS

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IIS

MVC

WCFServices

I have a Mvc App. I am trying to reach a https service.When I host the project with IIS express it works fine
In fact the problem is that my wcf client only works fine when Fiddler captures the packets ,strange but true....All the time I guarantee to close or abort connection by using "Using()" and call the method below inside the client's dispose method...

public static void DisposeServiceClient(ICommunicationObject client)
{
    if (client != null)
    {
        if (client.State == System.ServiceModel.CommunicationState.Faulted)
        {
            client.Abort();
        }
        else
        {
            client.Close();
        }

    }
}

By the way I am using proxy ,I have read about Fiddler changing proxy.The issue may be proxy but still couldnt figure out how to resolve it
http://stackoverflow.com/questions/4801189/httpwebrequest-doesnt-work-except-when-fiddler-is-running[^]

[Edited Question]