How to permanently remove 'HP Director' from the Dock

We bought a HP PSC 1205 all-in-one printer/scanner/copier from PC World a little while ago (a commando-like raid with a clearly defined mission: buy a printer; don’t engage with the idiot workforce; get out, quickly). The hardware seems pretty good for the money, but the bundled HP software is really bad.

My major gripe is that the HP Director item is added to the Dock on every reboot (or login). Having it put there on installation is almost excusable, but on every login? No! (I was going to link to something authoritative here that backs up my belief that items in the Dock should ultimately be under the user’s control, and software that installs Dock items willy-nilly is counter to some user experience guideline carved into a stone tablet somewhere, but couldn’t find anything; so it seems “anything goes”)

Luckily, a quick search revealed this MacOS Hint that fixes the problem by deleting the Director Docker application. Director Docker gets launched when you (or any user logs-in) and restores HP Director to the Dock. That works, but now your Mac is attempting to launch a non-existant application on every login. Here’s my tip: attack the root of the problem by editing the /Library/Preferences/loginwindow.plist file to remove the dict entry that launches the application.