MySQL (_not_ here)

(Big picture: small WinLAN; a client wants to use an app that sits on top of MySQL, so I install MySQL and their app on their Win2K server and go away. Time passes…)
Okay, they are now ready to use their app, and don’t know the MySQL passwords. I can’t find my notes either, so I go to their server, remove their app, remove MySQL, re-install MySQL -and it won’t run, complaining that it can’t find the hosts files.
Now, I deleted both the MySQL directory and the data directory, so why doesn’t the MySQL installer re-install the virgin hosts database with only the ‘root’ user?
Of course it’s operator error. The operator doesn’t see it, though! You guys use MySQL (one big reason we chose DH for our hosting; we will move our server stuff to DH Real Soon Now), maybe someone sees my mistake. Thanks!

Well, I could just cancel that post, but then no one else will learn from my mistakes.
The WinDoze version of MySQL allows you to tell it “Your binaries are here, but your data files are there”. However, the installer doesn’t care about that. It puts the user permissions database in [binarypath]\data\mysql, regardless of what YOU wanted. Thus, an important part of installing MySQL: If you want the data files somewhere other than inside the program directory tree, you have to 1) install the system, 2) set up the file location redirector file, and 3) move the internal data files the installer created, to[datapath]\data\mysql.
Otherwise it won’t start, because the user permissions table is “data” and you said it would be there.