TrakerJon has posted a Knoppix printing guide on the forums

Be sure you are booted into KNOPPIX and sitting at the default KDE desktop.

1) Open up a terminal (the little "shell" icon on the panel).
2) Type 'su' to switch your user to root.
3) Run the following command to enable the CUPS (Common Unix Printing System) daemon: '/etc/init.d/cupsys start'.

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