title: ContractFilter mismatch at the EndpointDispatcher exception
body: <p>I have the following scenario that I'm trying to test for:</p>
  
  <ol>
  <li>A common WSDL</li>
  <li>WCF endpoint that implements objects based on the WSDL and is hosted in IIS.</li>
  <li>A client app that uses a proxy based off the WSDL to create requests. </li>
  </ol>
  
  <p>When I make a web service call from the client to the service endpoint, I get the following exception:</p>
  
  <blockquote>
    <p>{"The message with Action '<a href="http://IMyService/CreateContainer" rel="noreferrer">http://IMyService/CreateContainer</a>' cannot be processed at the receiver, due to a ContractFilter mismatch at the EndpointDispatcher. 
    This may be because of either a contract mismatch (mismatched Actions between sender and receiver) or a binding/security mismatch between the sender and the receiver.  Check that sender and receiver have the same contract and the same binding (including security requirements, e.g. Message, Transport, None)."}</p>
  </blockquote>
  
  <p>I started using MS Service Trace Viewer, but not sure where to look. While looking at classes in client and the endpoint, they appear identical. </p>
  
  <p>How does one begin to debug this problem? </p>
  
  <p>What are some possible causes to this exception?</p>