How do I set up duplex printing on the HP 4200n printer?

Question

Seal

Hello, I have a problem with my HP 4200n printer.
The printers are on a different subnet behind the router because there aren't enough ip addresses.
The workstation has: Windows 7 + Office 2010.
Duplex printing was, but disappeared)
Reinstalled office 2010, cleaned the registry (office branch, also found a solution in toster), reinstalled the printer, deleted and added a route, installed a universal driver, and also shared this printer from another computer with the same printer did not help. Those. From all this it follows that the matter is in the computer. What can be wrong? )))

Answer 1

Look right-click on the printer --> Printer properties --> Device Settings tab --> Duplex module (duplex module) should be set to "Installed". I often encountered that in the presence of duplex, the value is "Not installed" and the printer refused to print on both sides.

Answer 2

Is "duplex unit" installed in the driver settings?