WCF Service Host cannot find any service metadata. This may cause the client application to run improperly. Please check if metadata is enabled. Do you want to exit?

In my case I got this error because the service name field did not actually match the namespace of the class actually implementing the operation contract in app.config file.

<services>
<service name="WCFHelloWorld.MySyncService" behaviorConfiguration="WCFHelloWorld.Service1Behavior">
.
.
.
</services>