My wife's machine, running 10.04, used to duplex print, but today it would not print. (My machine, running 12.04, duplex prints without problem.)

This may have happened some time ago, neither of us prints much. I tried changing drivers, but most would not keep the duplex setting under Print Options (make the change, click Apply, and it reverts to None). The drivers that do take the duplex setting won't print.

At this point, I'm thinking it would be better to clean out any and all printer configuration files and try a clean installation. But I have no idea where to find those files (searches have turned up nothing). Could I use Synaptic Package Manager to completely remove CUPS? or is there a better way? Or am I heading in the wrong direction?

I'm open to suggestions.