http://emperor.tidbits.com/webx/tidbits-talk
To Use a 990 Deskjet Printer in Duplex (2 Sided) in OS 10.6 (and maybe many others)--

Either load all the drivers from the installation disc or go to the following Apple web site and download all drivers for OS 10.6 (posted in a prior Tidbits article):

http://www.apple.com/downloads/macosx/apple/macosx_updates/macosxv1061update.html

After you install them, go to System Prefs and select the Print & Fax pane. Click on your printer then click Options & Supplies. Select Driver. Then under the pull down menu "print using" select printing software and find the Deskjet 9800 printer driver. Also, check the box for duplex printing, and select "Tri-Color, Black" as the ink cartridge. One thing I noticed is that in Page Setup for some documents the paper size indicates "US Letter Banner" instead of "US Letter". If this is the case, just select "US Letter" under the menu selection (otherwise the printer might not eject the sheet of paper all the way).

You should now have duplex capability......]]> Tue, 01 Dec 2009 08:12:35 GMT Web Crossing(r) Unix-v6.0 built Oct 8 2008 13:12:02 (source:1163 2008-09-24 11:42:21 -0700)/Macintosh-OSX-10.4-6.0 (http://webcrossing.com/) http://backend.userland.com/rss