Viv,

>I've been experimenting using XMLDataDocument as the parameter type. Oddly this won't get through the SOAP layer when passing it back to the .NET web service. If the type is specified as XMLElement it works fine. The only difference in the schemas generated is that the XMLDataDocument is mixed complex type. AFAIK this just means that the content *can* be mixed - not that it has to be. Don't know why this throws things. I'm using the webservices.htc and guessing the problem may lie there...

I don't think that's it. The SOAP parser knows about a few complex types like DataSet and XmlElement and performs custom actions on it. XmlDataDocument (or XmlDocument for that matter) aren't. This really shouldn't be a big deal from your end though since you can just pass the document element back and then on the other end simply reload the XmlDataDocument with this Xml... One thing that is nice that a lot of Soap Parsers can deal with Xml Elements directly so this is not just a .Net thing unlike soe of the other complex types like DataSet.