Help: Forgotten Password on Mac Pro

Hi,
I'm feeling very stupid about this as I religously keep copies of my passwords away from my computer, but I have forgotten the password for my new mac pro (not Macbook pro), and have not kept a record of it. And I can't work out what my very clever clue/hint means.

I'm running 10.4.9 and am wondering if the workaround that was suggested in another thread here for a Macbook pro will also work with my computer. I'm new to Mac and am terrified of doing the wrong thing.

The workaround, suggested by yeroen was
Boot into single user mode by holding down [Apple key] S at startup, then type:
passwd your sisters account name
at the prompt. This will prompt you for a new password. Once this is reset, reboot the machine normally by simply typing
reboot
which will bring the system back up in multiuser mode with the graphical login screen, and you're done.


I can't believe that I've done this; I always have stand-by's to save me from this sort of thing - if only I had followed my usual method of preserving the password.

Thanks for your help.

 

Thank you for this,
Will read it now, and yes, having just purchased the computer in Sept., I have the original installer CD's or DVD's.

Thanks,

 

Thanks very much for your reference links to the articles describing how to implement the change password option.

I followed these instructions, using the instal CD, and things went swimmingly (although I didn't follow up with the keychain password change yet).

Thanks once again and I am now about to store the new password information elsewhere so that at least I'll have it if I forget it in future.