HT4530 I just purchased an iMac and developed a user name and password. I'm trying to install a program but can't because I forgot that information and didn't write it down. How do I reissue a new username and password

Question

I just purchased an iMac and upon setting it up I initiated an username and a password.  Unfortunately I didn't write it down and now I'm trying to add software and the system won't let me because I forget that info.  How do I reissue a new usernam and password?

Answer 1

Boot from your recovery partition by holding down the key combination command-R at startup. Release the keys when you see a gray screen with a spinning dial.
When the recovery desktop appears, select Utilities ▹ Terminal from the menu bar.
In the Terminal window, enter “resetpassword” and press return. A Reset Password window opens.
Select your boot volume if not already selected.
Select your username from the menu labeled Select the user account if not already selected.
Follow the prompts to reset the password.
Select  ▹ Restart from the menu bar.
You should now be able to log in with the new password, but you won't be able to unlock the Keychain. If you've forgotten the Keychain password (which is ordinarily the same as your login password), there's no way to recover it. You’ll need to reset your keychain in the preferences of the Keychain Access application.