Mac air 4GB 1600 mHz DDr3
Intel HD Graphics 5000 1024 MB
OS X 10.9.2 (13C64)
I have forgotten the names and passwords for administrators on my computer.
I need them to install a new printer
MacBook Air, OS X Mavericks (10.9)
Your username is the name you will see below your Home folder that you find in the /Users/ folder. If you forget your admin password then:
Forgot Your Account Password
For Lion, Mountain Lion, or Mavericks
Boot to the Recovery HD:
Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.
When the menubar appears select Terminal from the Utilities menu.
Enter resetpassword at the prompt and press RETURN. Follow
instructions in the dialog window that will appear.
Or see:
Reset a Mac OS X 10.7 Lion Password
OS X Mountain Lion- Reset a login password,
OS X Mavericks- Solve password problems,
OS X Lion- Apple ID can be used to reset your user account password.
How to change administrator names and passwords
