Hi,
that sounds like it should work, is the printing application installed on the server?
The /printfile parameter will print the file from the associated application.
Maybe it will help to find the problem, if you set the logging level to “trace” in the debug section of the application settings, print something and post the log here or send it to support(at)pdfforge.org and we will gladly have a look at it.
Best regards,
Robin