22.214.171.124.2 Mapping Remote Method Invocation Reply
The encodingStyle attribute SHOULD be written as part of the SOAP Envelope element with a value of http://schemas.xmlsoap.org/soap/encoding/.
The implementation MAY add implementation-defined SOAP header elements (children of the soap:Header element) to the SOAP response in order to transmit implementation-specific information to the client. Any implementation-defined SOAP header elements SHOULD use the namespace "http://schemas.microsoft.com/clr/soap/messageProperties".<39>
If the method resulted in an Exception, then the Exception MUST be encoded as a SOAP fault as specified in the Mapping Exception section.