If you are not re-generating the operation code then I wouldn't be worried to change it if required.

The implementation class will be on the adapter..

So if for instance you change the SOAP version (should that make a difference) then it could be done with

First though, I would enable the SOAP log and compare the headers to your working SOAP UI headers.

Maybe try...

Hi Kurro,

Some random suggestions without being able to see the implementation details...

1. Enable the SOAP log and compare the request and response headers to SOAP UI to see what is different

https://docs.intersystems.com/latest/csp/docbook/DocBook.UI.Page.cls?KEY=GSOAP_debug#GSOAP_debug_info_soap_log

2. Does changing the SOAP version make any difference

https://docs.intersystems.com/latest/csp/documatic/%25CSP.Documatic.cls?LIBRARY=%25SYS&CLASSNAME=%25SOAP.WebClient#PROPERTY_SoapVersion

3. The error is probably raised in this block of code, might be worth working backwards from there, its at the end of DoSOAPRequest in %SOAP.WebClient

    Set responseContentType=$zcvt($piece(response.ContentType,";",1),"L")
    If ..SoapBinary {
        If (responseContentType'="application/octet-stream") Quit $$$ERROR($$$SOAPUnexpectedType,response.ContentType)
    } Else {
        If (responseContentType'="text/xml") && 
           (responseContentType'="application/soap+xml") &&
           (responseContentType'="multipart/related") {
            Quit $$$ERROR($$$SOAPUnexpectedType,response.ContentType)
        }
    }

4. If your running out of ideas then maybe reinstall / restart the server code (is it .NET by any chance)?