How can I fix “Conversion from SOAP failed” fault while consuming mainframe web service in VB .Net web service?

Question

I'm currently working on a VB. Net web service calling another web service running in the mainframe. I was provided with the WSDL file and I generated a proxy class using wsdl.exe. Upon attempting to invoke the method of the mainframe web service using the proxy class, I encountered an exception saying "Conversion from SOAP failed" coming from a line of code in the generated proxy class.

Dim results() As Object = Me.Invoke("WSIBACTPOperation", New Object() {WSIBACTPOperation1})

Any idea what is causing this? I was told that I don't need to use any certificate. How do I fix this?

Answer 1

Figured this out myself. The web service was only requiring COMPLETE AND CORRECT INPUTS. The developer on the customer's side made a mistake when she told us that some of the inputs were not required and therefore can be left blank. Double-checking the WSDL file solved the problem.

Answer 2

First, look at the SOAP message coming back from the mainframe. Does it look like a SOAP message, or does it look like HTML or plain text indicating you aren't authorized?

When you were told you didn't need to use any certificate, were you told you should use BASICAUTH?