OL Learn

SOAP Client: Error NULL-Object



I try to catch data from a SOAP server, using the workflow plugin “Soap Client Plugin-in”.

I have entered the WSDL address and successfully get the service and the associated methods displayed. When I execute the process, I always get an error message:

[0003] W3001 : Error while executing plugin: Exception executing method: Exception while looping through soap methods: Das NULL-Objekt kann nicht in einen Werttyp konvertiert werden. | inner exception:

The german part of the error message in english:

The NULL object can not be converted to a value type.

Does anyone have any idea which NULL object is meant?



Do you know if the SOAP version you are “connecting” to is version 1.1 or later?


No, I do not know the SOAP version. I only know that the first entry in the API documentation is from 2011, so I can not believe they use version 1.0.


Open your WSDL link in Internet Explorer…search for a value in the returning XML like SOAP11 or SOAP12 in the definitions. That should tell you what version of SOAP is being used. Unfortunately, it is not always there.

Note that only SOAP 1.1 is supported with our plugin. Anything more recent will crash.


It should be version 1.1 because the header includes namespace: http://schemas.xmlsoap.org/wsdl/soap/

According to stackoverflow that is an indicator (https://stackoverflow.com/a/18968668).


Could it be that one or some of the Workflow variables you pass to a function is empty? Or there is a typo in it?


I do not use variables, I use static values.
My first thought was that a required field is not filled, but I have filled all required fields in the correct way (according to the API documentation from the customer).


At this point I would suggest to review the API with the client or to open a call with our technical support through our website.

Hopefully, the WSDL will be accessible from our location so they can reproduce it and help you.

Best regards,


Thanks so far. I will open a support ticket.

But another question to this:
Can this error message possibly be due to an empty response from the server?
For each submitted request (Workflow debug mode), a .env file is stored in the directory C:\ProgramData\Objectif Lune\PlanetPress Workflow 8\PlanetPress Watch\Debug\file (but only when the option “Use returned raw SOAP packet as new data file” in the “Soap Client Plugin-in” is checked). Each of these files are empty…

Additional Informations:

I installed the program SoapUI to check the request and the response. There I did not get the correct response (instead I get a html source code). So, I changed manually the target url from automatically identified “https://tickeos.de/” to the right target url “https://railandfly-qs.tickeos.de/service.php/kombiticket_db”. After that change I get the correct response in SoapUI.

Is there a possibility in Workflow to set/change the target url? I can only find the possibility to set the WSDL adress.


I suggest you ask that question as well to our Support team as they will enquire this with our R&D. I do not know the answer but I don’t remember seeing a setting to would allow what you are asking for.

The plugin only display the function returned by the SOAP server and their properties and methods. If none are returned, then my guess is that it isn’t available.


Maybe anyone has a VBScript example for Soap requests with authentication?