This will walk you through how to reset your admin password. This is helpful if you have forgotten your admin password or you have got a mac with an admin account on it that no one knows the password to.
NOTE: This is for OSX 10.4/5/6
Step 1: Boot into Single-User mode (Command + S)
Step 2: After boot Run your fsck -fy command
Step 3: Mount your main volume with mount -uw /
Step 4: Type in the following command: rm /var/db/.applesetupdone This resets your setup status on the mac and allows you to create a new ID
Step 5: Setup your new admin account
To Reset the original Admin Account
Step 1: Open System preferences – Go to Accounts
Step 2: Click the lock, enter the password you created with the new admin account
Step 3: Go to the current admin account and click reset password. We recommend to also reset the keychain password as well