I have an old computer of mine (the first MacBook Pro model) that I'm trying to wipe clean and repurpose. But back in the day, I was quite security conscious, and my own barriers are foiling me:

  • The account I used daily was not the administrator
  • The admin account used a different password
  • I set a firmware password on it

I can log into my old account that I used every day, but I can't remember the admin password or the firmware password. This means I can't boot to target disk mode or to an OS X install DVD.

My goal is to reinstall the OS. I've already saved all the data I need. I know I can remove the hard drive, put it in an enclosure and wipe it with another computer, but I'd rather not go that route until I have to, since it's a big pain with that model of MBP (I did it once before). Any ideas?

2 Answers 2


You can remove the firmware password by changing the RAM configuration, booting up to the startup menu, shutting down and changing it back. Basically, if you have two 1GB chips of RAM in there now, you can remove one of the chips, start up holding alt/option, shut down and put the other chip back in. This will remove the firmware password.

Now, you can follow these instructions for doing the erase and install.

Good luck!

  • This worked like a charm. Jan 15, 2012 at 20:56
  • Great! Good luck.
    – Matt Love
    Jan 15, 2012 at 21:40

If you have the install discs you can reset the admin account passwords and wipe all data.

First the passwords.

  1. Insert the disc, choose you language.
  2. In the installer/utilities (depends on your OS version) menu you choose reset password and then choose the Mac HD.
  3. Choose the user account, enter in your new passwords.
  4. You then need to quit the password changer app.

Now the wipe.

The process is pretty simple and runs as follows:

  1. Insert the install CD and reboot the system.
  2. Hold down the C key directly after you hear the startup sound.

  3. Once the installer appears, select “Open Disk Utilities” from the Installer menu.

  4. In the left device menu select the drive you wish to securely erase.

  5. Click the “Erase” tab in the window that loads on the right.

  6. Choose the HFS+ format from the volume format drop menu options.

  7. Click the “Options” button and select the “Zero All Data” checkbox.

  8. Click OK and then Erase.

  • this is great...except you can't do it until you remove the firmware password. @Mr.Jefferson See my answer for these instructions.
    – Matt Love
    Jan 15, 2012 at 20:40
  • Remember, I can't boot to anything but OS X on the local disk because the firmware password is set. Jan 15, 2012 at 20:41
  • @MattLove yep, I missed that bit. Jan 15, 2012 at 20:43
  • @GraemeHutchison no worries!
    – Matt Love
    Jan 15, 2012 at 20:44

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