How to handle incorrect SOAP fault in WCF?

Question

I have to consume to a third-party web service using SOAP. It was easy to get it to work with WCF, but now I have a problem with SOAP faults. The service sends me an incorrect SOAP fault:

<?xml version="1.0" encoding="utf-8" ?>
<SOAP-ENV:Envelope 
    SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" 
    xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
    <SOAP-ENV:Body>
        <SOAP-ENV:Fault>
            <SOAP-ENV:faultcode>14</SOAP-ENV:faultcode>
            <SOAP-ENV:faultstring>Unknown Function</SOAP-ENV:faultstring>
        </SOAP-ENV:Fault>
    </SOAP-ENV:Body>
</SOAP-ENV:Envelope>

The error is that the <faultcode> must not have a namespace:

System.ServiceModel.CommunicationException : Server returned an invalid 
SOAP Fault. Please see InnerException for more details.
    ----> System.Xml.XmlException : Start element 'faultcode' from namespace 
    '' expected. Found element 'SOAP-ENV:faultcode' from namespace 
    'http://schemas.xmlsoap.org/soap/envelope/'.

I can't change the original web service - but is there anything in WCF I can use to still handle these fault messages in some way without getting CommunicationException all the time?

Solution

Yes, but it's not exactly elegant. See the message inspector code at the bottom of this forum post:

http://social.msdn.microsoft.com/Forums/en-US/wcf/thread/435850aa-bf74-4158-a29a-256135207948

Basically, you can take the incoming message and alter it so that it can be handled by WCF.

Comments

[chris166]

Thank you, that was exactly what I needed! And it's elegant enough :)