you might want to check out the HP web site for the latest drivers for the 842C. HP are very proud of the fact that there are a bunch of printer drivers included with OS X but the problem is that they are Print Only drivers and do not give the added extras, like double sided printing.
Before you install the new driver, delete the old printer from your printer setup utility. Then install the new driver.
Check out the Epson website too.
P
Has anyone performed double-sided printing using OSX? I have a Mac Mini running OS10.3.9 and an HP842C printer and a RX500 Epson all-in-one. In classic mode I'm able to print double-sided from all my OS9 applications. When I print from OSX applications the double-sided option is grayed out, so can't print double-sided other than manually by printing the even and odd pages. I would really like to know if anyone has successfully printed double-sided usiing a real printer and OSX (10.3.9).
Thanks in advance.

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