[CentOS] OT: default password for HP printer

For some reason the "tech support" people at Hewlett-Packard don't know what the default password is to access their printer's embedded web server (EWS). I got it myself from the installation manual six months ago and immediately set my own password which I have used since then, so I no longer remember what the default is. (It's really a longer story than that, but....) So I was just hoping that someone here might know what that default password is. Mine is an Officejet Pro 8620, but perhaps some other, recent HP printer default password would work. (Yes, I've already tried various versions of "admin", an empty password, and others, but just not anything which has worked.)