Here (USB-to-parallel cable, LaserJet 2100) the update apparently works only if the printer is turned on while plugging USB in. Turning the printer off for a while and on again, the connection is gone. Cycle the USB plug while the printer is on, and the connection re-appears.
Here (USB-to-parallel cable, LaserJet 2100) the update apparently works only if the printer is turned on while plugging USB in. Turning the printer off for a while and on again, the connection is gone. Cycle the USB plug while the printer is on, and the connection re-appears.