BleepingComputer.com: This Printer Is Making Me Nuts

I'm pretty sure, at this point, that this isn't a printer issue. I'm starting to think it's a Vista issue.

I have a computer at my office that randomly - like, in the middle of a print job - will "uninstall" it's printers. Restarting brings the printers back.

We have a couple Canon printers to handle large print jobs, an HP 5 in 1, and a Lexmark connected directly to her computer. The print spooling software fails pretty consistently too. I'm sure you need more information than this to lend a sister a hand, but I don't know exactly what info you need - so some specifics would rock and I can answer from there.

Thanks ahead of time to anyone who has a direction they can point me in.