Passing custom classes to a web service

This article can help you: http://www.dalepreston.com/Blog/2005/02/passing-classes-from-webservices-part.html

Basically, you need to do the following in the file Refence.cs:

1) Delete any references to XmlIncludeAttribute
2) Qualify your classes with the correct namespace (if necessary)
3) Remove the custom class declaration (I had to do this since I already had the class defined in my VS solution. In other words, I had access to the custom class in both the client and server application).

The other option is to write the proxy classes yourself, but I didn't try this.