Yes, there are settings not affected by the "Restore Factory Setup" option in the LaserWriter Pro 810's control panel. This option only affects settings used by the PostScript interpreter. Settings for the LaserWriter Pro 810's print server (otherwise known as Virtual Printer Technology) are kept on the print server card itself which is inside the printer. It has its own separate Non-Volatile RAM (NVRAM). These settings can be reset in two different ways.
1) By entering the command "INIT DEFAULT DELAY 0" through the printer's Remote Console Facility (RCF).
2) By putting a jumper on "WIRE 2" on the print server card, starting up the printer until "Ready To Print" appears, and then removing the jumper.
WARNING: Either one of these reset mechanisms will remove all virtual printers, and any settings related to virtual printers.
Here are some suggestions which may cure your problems in printing from the UNIX default socket:
1) Reset the LaserWriter Pro 810's print server as mentioned above.
2) Through your printer's RCF, type in "show service characteristics" and look to see that CONNECTIONS and QUEUE are "enabled" in TCP port 3101. If they aren't, enabling them should cure your problem.
3) Print to a different TCP port, such as 3104 for ASCII printing or 3102 for PostScript printing.