I finally found a reference to this issue elsewhere online - seems to occur when you have a non-UTF8 local. Cups tightened up it's char set handling (1.3.4), and supposedly hplip is at fault. Here's a simple workaround to demonstrate: Me before: LANG=en_CA hp-toolbox detected nothing Me now: LANG=en_CA hp-toolbox now sees the printer LC_ALL=en