At issue is whether the printer can accept Postscript directly. If yes, then the job goes to the printer directly. If not, the output needs processing. A tool called Foomatic processes the postscript into raster, using Ghostscript to do that. Then the output goes through CUPS to hpijs, the hp-provided inkjet interface. From what I can find, Apple moved CUPS, which causes Foomatic to fail. The fix I found is supposed to fix the problem by putting CUPS where Foomatic expects it, which did make the error go away, but for me left the Foomatic- Ghostscript-CUPS-hpijs string broken. As the printer is a unique label printer we needed for our business, it was a better business decision to stop wrestling with it and just go with Parallels and Win7. We already had Parallels, and I got a discount on a brand new Win7, so all is good.