If you ever forget your Administrator password or the password to a normal (non-admin) account on your Macintosh there’s a simple way to reset your password. As long as you have the OS X install DVD/CDs or the restore CDs/DVD that came with your computer.
Stick the DVD into your computer and reboot. Hold the Apple+C while rebooting. This will cause the computer to boot from the DVD. Click on the Installer menu item (located at the top of your screen) and go to Reset Password. Choose the Macintosh HD and then you’ll be able to select the user account you want to reset the password on. Make sure NOT to choose the ‘System Administrator (root)’ account!! Input a new password for the account, hit save and reboot the computer. You should now be able to login with your new password…
There’s one last thing we should do. You might notice that you’re getting a message/pop-up window that is asking for your “login” keychain password. To get rid of this we’re going to open up the ‘Keychain Access’ application (found in Applications >> Utilities).
You should be aware that this will remove any stored password you have, for example if you use Mail and have kept your password saved, that will be removed. If you use iChat and have iChat auto-save your password, it will remove that too.
Now in Keychain Access click on Edit from the menu bar (top of your screen) and choose ‘Keychain List’ from the menu that comes down. A new windows pops open. Select ‘login’ (has an icon of one person) and delete that. Reboot your computer and you should be set.
Hopefully you’ll never have to reset your password, but in case you do this guide should walk you through the process. It’s a good idea to make strong password that no one will guess but make it so that you can remember it!
Useful Resources:
Changing or resetting an account password
Keychain Access asks for keychain “login” after changing login password
Deleting a keychain