The Macintosh Print Pack does not support HP 500 series printers. The only drivers that the Print Pack supports are those that provide full Epson Emulation. The HP printers do not support Epson Emulation. There is a full list of printers supported in the Print Pack documentation.
If you need this functionality for HP products, GDT Softworks, supports some additional drivers including those for HP printers.
The Tech Info Library article titled "Locating Vendor Information" can help you search for GDT Softworks' address and phone number.
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