It is possible to call web service from VB6 using Soap Toolkit 3.0. Soap Toolkit works the best when calling Web services created using Soap Toolkit 3.0 and COM objects. This is because Soap Tookit 3.0 comes with the WSDL tool that can generate both the WSDL and WSML files. The later is important in deserialze the soap message and map it to the COM objects on the client-side.

What happens to Web Services not created with Soap Toolkit 3.0? Those web services do not have WSML files. So we can either create WSML manually or create the customer mapper. The later essentially requires to walk through the IXMLDOMNodeList returned by soap call and create and set the properties of COM objects.