Duplex printing for Windows XP
You need to "tell" your computer that the printer can handle double-sided printing. To do so:
Start Menu: Settings: Printers and Faxes:
Right click the printer you want to change, select Properties.
Click the Device Settings tab.
At the bottom of the list, below Installable Options, click the Not Installed link next to Duplex Unit. Change that to Installed. Click Apply.
If you want double sided printing to be the default, click the General tab. Click the Printing Preferences button.
For Print on Both Sides select Flip on Long Edge, then OK, OK.
Duplex printing for Max OSX
You need to "tell" your computer that the printer can handle double-sided printing. To do so:
Open System Preferences, click Print & Fax.
Select the printer you want to change in the list on the left. Click Printer Setup.
From the pull down menu select Installable Options. Check the Duplex unit box, then Apply Changes.
To make double sided printing be the default open Microsoft Word. Select File: Print.
From "Copies and Pages" select Layout.
At "Two Sided" select Long Edge Binding.
From "Presets", select Save As and name this configuration Duplex. Then whenever you print you can choose Standard or Duplex depending on which you want.