By default, 'Auto Print Order' uses an internal system to print your documents, but sometimes you prefer to use an external program to get a different rendering, that's the reason you can force 'Auto Print Order' to use the default Windows program to view and print PDF.
Instructions to set this option
Step 1: Go in the options of 'Auto Print Order'
At bottom left of the application click on 'Settings'
Step 2: Go in the section 'Advanced'
- Unset the option 'To print PDF attachment, use the internal program...'
Step 3: Make sure you have an application to read PDF installed on your computer.
IMPORTANT: If you use external program to print PDF, it will not work when 'Auto Print Order' runs in service mode (When no user is logged to Windows), it can work only when you are logged to Windows.