I sold a 2008 Macbook Pro 17" to someone on Ebay. I had installed a clean copy of Mavericks over wifi using my apple ID. I created a user and logged in so I could take photos of the screen for the Ebay auction. Buyer has laptop now, and can't do a fresh install (or even login) without my admin password. I've given him every version of my passwords I can think of, but he says none of them work. Any advice on how he can fresh install maybe using his apple ID? He's pissed and wants to send it back. Help!