I am building a application that will expose some functionality using WCF web services.
I have a data class that is used throughout the app that I now want to use in the web services (I have simplified the below just for example). The trouble I am having is working out how to use the data class in the web service without including it in the interface as a DataContract. Im having a real blonde moment (no offence to blondes) and cannot figure it out.
So my solution:

My Web Service:

Web Service Interface with the Data Contract declared here all is fine:

But I want to use the ErrorRequest in DataClasses
