I have an Oki Laser C5250n with duplex unit connected by USB to my WIN 7 Pro PC. I used the Oki Vista drivers
to get the printer working and all is fine except for the duplex option.
When I right click on the Oki C5250n device - select Printer Properties - Device Options Tab - Tick box for Duplex Unit - click apply and ok. Then under Printing Preferences I still can't select 2-sided printing.
When I repeat the above I find that the box is unticked and won't stay ticked.
Can anyone suggest why this shoud be happening. I had no probs on an XP machine.