Do you have a question about the HP Laserjet,Color Laserjet 4200dtn and is the answer not in the manual?
Unpack the duplexer, prepare the printer by turning it off, and insert the unit into the slot.
Turn the printer power on after the duplexer has been properly inserted.
Configure the printer driver in Windows to recognize the duplexer for full functionality.
Print a configuration page from the control panel to confirm the duplexer is recognized.
Select duplex or two-sided printing from your program or printer control panel.
Find support information and note that the auto-cleaning page function is unavailable.
Detailed steps to safely remove the duplexer unit from the printer by turning it and pulling.
Reinstall the slot cover onto the printer if the duplexer unit is no longer attached.
Consult the CD-ROM use guide for access to printer driver, control panel, and problem-solving.