Error Handling in WCF WebHttp Services with WebFaultException only xml formated exception
I found the solution; faultExceptionEnabled needed to be false. Now I get the exception in json.
minor changes in Web.config service setup should work too: automaticFormatSelectionEnabled="false" defaultOutgoingResponseFormat="json"
<system.serviceModel><serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true" /><behaviors> <serviceBehaviors> <behavior> <serviceMetadata httpGetEnabled="true" /> <serviceDebug includeExceptionDetailInFaults="true" /> </behavior> </serviceBehaviors></behaviors><standardEndpoints> <webHttpEndpoint> <standardEndpoint name="" helpEnabled="true" faultExceptionEnabled="true" automaticFormatSelectionEnabled="false" defaultOutgoingResponseFormat="Json" /> </webHttpEndpoint></standardEndpoints>