I purchased a MacBook Air from someone 4 months ago and everything was working perfectly. There is no user name or password needed to log in and I've never had problems using it.
Now I would like to reinstall OS X but I can't do it because it's asking for a firmware password when booting with Option ⌥ held down. It's 4 months now and I've lost the seller's phone number to ask for password.
I've tried to reset NVRM but those keys are disabled. I can't boot from external HD when I turn on the system. What is the reset procedure?
Best Answer
To reset the firmware password it looks like you have to take it in for service at your nearest Apple Support location as noted in the following Apple Support Article MacBook Air (Late 2010) and later, MacBook Pro (Early 2011) and later, iMac (Mid 2011) and later, Mac mini (Mid 2011): Recovering a lost firmware password
As a side note you will need the original proof of purchase.