Issue exposing an orchestration as a wcf service

You built your orchestration, deployed it and tested it with a file port everything works fine.... cool

now you want to expose the orch as a wcf/asmx service, we launch the wcf publishing wizard and after specfying the name space you find that there are no public ports, ok, we go modify the the preceive port to Public and then launch the WCF Publishing wizard again, we still get the same error message,,,,,,

I wonder why??

Resolution:
un gac the orchestration assembly and then we try again, still the same error

I wonder why???

Restart visual studio and open the project and viola we can publish the orch as a service now,......