Behavior:
You have developed your own Web Service with your own Namespace and want to use it in a Workflow. The Eb Service works correctly, when you open it in the browser and it is configurable in the Workflow Designer as well.
But if the Web Service is triggered in a actual Workflow, it does not return any result.
Solution:
One possible solution for this behavior is follwoing:
If you use your own Namespace in the Web Service, you have to make sure, that the Namespace closes with "/". See the default-Namespace in our Sample Web Service: "http://tempuri.org/"
The cause why it seems to work in the Workflow Designer but nit in the Workflow itself is located in the database. The configuration for every workflow step is saved in here. If the Namespace is not closed with "/", the database entry is not build correctly and therefore, the call is not processed when the Web Service is triggered in the Workflow.
