i forgot my login password at start screen
how can i get my password back i cant login on start page
MacBook Pro with Retina display
Lion / Mountain Lion
User Password?
http://support.apple.com/kb/PH11390
Administrator Password?
Follow the instructions in the beige and green boxes.
http://pondini.org/OSX/Password.html
Note
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.