Courier vouchers are issued in pdf format. In order to print them automatically on the default printer, a pdf printer software must be set in courier.ini file (in EMDI root folder). Any pdf reader that supports print via line command can be easily used.
For example:

 

Ghostscript

To print automatically it must be configured in the courier.ini file, located in the main EMDI folder:

for help:

PDF24

for help:

https://creator.pdf24.org/manual

Foxit Reader

Bullzip PDF Printer