In an XML Web Service and WCF service, the server side will return any unhandled exception as
SoapFault in the returned message. For WCF service operations, exceptions are returned to the client through two steps:
By default, WCF will return the simple error message or complete exception information (including Callstack) as the Fault content. However, sometimes we want to encapsulate the raw exception information or return some user-friendly error to the client side. To support this kind of customized exception-information format, WCF has provided the
FaultException features. ...