My HP Laser Jet 4MP (the best they ever made then or now) is hard to give up. BUT, I also have ongoing problems with it disappearing from the chooser. LaserWriter8 is set as default icon, but when I click on that nothing comes up in the right hand box. I have had 3 different "experts" reset the connection...works for a while (a few weeks to a few months) then bingo--gone again! I'm in the process of selecting a HP 1200 printer, since it's the only one that lets feed in single sheets/envelopes, BUT, it is way larger than my old HP (taking up desk space instead of neatly stowed below the desk).
I've also tried the two suggestions listed without success (the "experts" confess to not really knowing exactly what they did that worked, since they tried so many combinations of pulling plugs, deleting files, reinstalling files, etc.
AND, I've love to know if anyone has had any permanent success or suggestions.