WCF MetaData not working - wcf

Question

I have tried several times to have my WCF service expose MetaData. Instead, I keep keeping the exception:
The contract name 'IMetadataExchange'
could not be found in the list of
contracts implemented by the service
SecurityBroker. Add a ServiceMetadataBehavior to the
configuration file or to the
ServiceHost directly to enable support
for this contract.
... when manually browsing to the service using IE.
(I am presuming this is the same reason why my client application isn't able to generate a service reference. Baby steps and all)
And yet my web.config looks okay:
<system.serviceModel>
<serviceHostingEnvironment aspNetCompatibilityEnabled="true" />
<behaviors>
<endpointBehaviors>
<behavior name="webHttpEnablingBehaviour">
<webHttp />
</behavior>
</endpointBehaviors>
<serviceBehaviors>
<behavior name="webHttpEnablingBehaviour">
<serviceMetadata httpGetEnabled="true" />
</behavior>
</serviceBehaviors>
</behaviors>
<services>
<service name="IWW.MIGTurbo2.WCF.Security.SecurityBroker">
<endpoint contract="IMetadataExchange" binding="mexHttpBinding" address="mex" />
<endpoint address=""
binding="webHttpBinding"
bindingConfiguration="default"
contract="IWW.MIGTurbo2.WCF.Security.ISecurityBroker"
behaviorConfiguration="webHttpEnablingBehaviour">
</endpoint>
</service>
</services>
<client />
<bindings>
<webHttpBinding>
<binding name="default" />
</webHttpBinding>
</bindings>
</system.serviceModel>
So I have my IMetadataExchange contract defined with mex fine, and hooked up, as far as I can see. Have I missed something daft?
Edit
My Service definition is shown below, if this is useful:
<%# ServiceHost Language="C#" Debug="true" Service="IWW.MIGTurbo2.WCF.Security.SecurityBroker" Factory="System.ServiceModel.Activation.WebScriptServiceHostFactory" %>

Answer 1

Your config file has the behaviorConfiguration attribute on the "endpoint" element, but you also need it on the "service" element.

Answer 2

I am using NetTcpBinding for all. In my case I was having the same issue and resolved it by adding:
(a) a behaviorConfiguration="" to the mex endpoint
<endpoint address="mex" binding="mexTcpBinding" contract="IMetadataExchange" behaviourConfiguration="" />
(b) a behaviorConfiguration="mex" to the service definition:
<services>
<service name="AcmeService" behaviorConfiguration="mex">
(c) The behaviour entry
<behaviors>
<serviceBehaviors>
<behaviour name="mex">
<serviceDebug includeExceptionDetailInFaults="false"/>
<serviceMetadata />
</behavior>
</serviceBehaviors>
</behaviors>