If you don’t provide a dictionary to read the XML stream with, you will get a weird and unhelpful exception that says “the input source is not correctly formatted”, and googling around will only bring you to posts telling you that “your client/server endpoints are not matched” or “you need to use the basicHttpBinding”. This is not a binding issue – it’s a deserialization issue that comes up when i make an attempt to inspect the soap messages coming in to (or going out of) my WCF service.