Just in case anyone else is going through the pain of Delphi to .net WCF service then you may be interested in how I fixed my problem. The unit that is created when you import the WSDL has some lines of code in the initialization section. One of them may look like this “InvRegistry.RegisterInvokeOptions(TypeInfo(IUse rImageService), ioDocument);”. The cause of my problem was that “ioDocument” was actually set to “ioLiteral”. When it was set to ioLiteral the SOAP envelope XML wasn’t formed in a way that the WCF service was expecting. Once I changed it to ioDocument the XML was created differently and matched the XML created by the Visual Studio WCF Test Client. It now works but this was a very unpleasant experience due to the lack of help and documentation.

Thanks for all your help

Ian