How can I hack an old imac?

[MonksMac]

Try holding down the shift key while the computer starts. Maybe that will help you get around the password. If you start from the CD the OS X password wouldn't have any effect on OS 8? Are you positively sure you started from OS 8 and not OS X. OS 8 has a dark grey look.

 

[iMpathetic]

So, from what I understand, OS X is already installed on this iMac. If there is an administrator password he can't get through, hold down Command-S while booting. White text will scroll on a black screen. Wait until it finishes booting. Then type: passwd whatever the name of the account is and it wil tell you to enter a new password. That should help.

 

[FoolofaTook]

Ok, I had the same problem. They have a Community Cleanup Day here in my town and someone left an iMac OSX on the pile. So I grabbed it because my son is a Computer Engineer and I figured he could make it work or turn it into Unbuntu or a Chromebook. Well, he doesn't have any time, so I tried. I have the same problem as you. The guy who threw it away did not log out or erase the hard drive. His stuff is on it. So I tried to erase the hard drive, but I cannot because I would need his password. I looked online and found a way to use it by hacking into it using command s and setting up a new account, but he is still a user and controls the security and utility. All I wanted was to play around with it and get rid of his account so his stuff is not accessible, but no luck so far.

 

[KeesMacPro]

If there's a firmware password you could try the following:

1- remove 1 of the RAM sticks
2- power it on and keep pressing Command+Option+P+R until you've heard the chime 3 times (triple PRAM/NVRAM reset).
Let it boot and shut it down.
3- reinstall the RAM stick
4- boot from an installer disk/USB , erase the internal disk and start the installer.

If you want to delete other accounts , creating a new user account with admin privileges is all you need.
Login to your new admin account and go to: preferences> users&groups > unlock > click on the old account and click the minus button.

Solved--Create New Admin Account on Mac When Cannot Sign in