How to avoid authentication screen when invoking a process?

Hello!

I created a simple webservice in Workbench to generate a sequential ID for PDF forms.

It's working fine, but the form is open a Windows Security dialog asks for login and password to access the webservice.

As there are over sixty of these forms to be used by around 4,000 employees, this will be a major problem.

Question: is there a way of invoking the process and sending the authentication information when the form is opened and thus avoid this dialog entirely?

Thank you very much for any hints!

Marcos