Erase and Completely Reset Your Mac

If you are about to sell or give away an old Mac, it is important to erase it completely and reset it so it is exactly as it was when you first bought it. It is important to remember to sign out and remove all accounts and services first, then erase the drive, and then use Internet Recovery to install its original operating system.

Comments: 28 Responses to “Erase and Completely Reset Your Mac”

    Claire
    3 years ago

    I forgot to sign out of everything what do I do now reply as soon as possible please thanks Claire

    3 years ago

    Claire: Details? Did you give away/sell the Mac? Did you erase the drive first? If not, what, exactly, did you do? How long ago? What things do you use? (iCloud, iTunes, Facebook, etc, etc).
    If you erased the drive then the worst you will have to worry about are just annoyances, like needing to deauthorize and re-login. Things like that.
    But it is always a good idea to change your passwords for everything: Apple ID, FB, everything. You should do that every once in a while anyway, so look at this as a good excuse to prioritize it.

    Jean-Claude
    3 years ago

    Why is it necessary to log out or delete all accounts if you are going to erase the hard drive anyway?

    3 years ago

    Jean-Claude: It is useful to alert those services that you are no longer using that device. For instance, with Adobe, it allows you to install software to two machines. If you don’t sign out, it thinks you are still using that machine for one of the two installs. For iTunes, you have a limited number of “authorized” devices. Deauthorizing will give you back one of those devices. In the past, iMessage has continued to try to send messages to hardware because you never “closed” the relationship between the service and the computer. It only takes an extra minute and is worthwhile to make sure to log out and remove all accounts.

    Jeff
    3 years ago

    I bought a Mac that was still showing the old owner’s Apple ID. Can I use this information to change it to my Apple ID or do I have to have the old users Apple ID password?

    3 years ago

    Jeff: You should NEVER use someone else’s Apple ID. It is a bad idea for your sake, their sake, plus it is pretty much identity theft.
    You should wipe it clean and start fresh. Back up your documents first, of course. Visit the Genius Bar if you want to make sure it is done right.

    Carol
    3 years ago

    Is it worth going through this for an old MacBook 3, with 3 user accounts, that we have already replaced? It is in a closet and has a battery that will not charge, only works when plugged into power, but has lots of confidential info on it. Other choice is to take it apart and chop it up. We’ve upgraded since then!

    3 years ago

    If you are never going to use it again, then yes, why not? Especially if you haven’t used it in a while and know that you don’t need anything on there. Erase the drive. Use the “security”options in Disk Utility when you erase it so it overwrites the bits on the drive. Then take it in to be recycled. In that case, no need to go beyond the erasing state and bother with installing an OS.

    Anthony
    3 years ago

    Gary. My prior Mac Desktop (3 yrs ago) quit running and left me with a screen that looked like a blue striped oxford cloth shirt. Nothing else showing. Mac Genius people said hard drive was “gone.” Been meaning to give to electronics recyclers but concerned about someone being able to retrieve old data: medical – legal. I doubt your proposed erase will work. Suggestions?

    3 years ago

    Anthony: Can you mount it as a target disk? https://support.apple.com/en-us/HT201462 If so, then you can use Disk Utility to erase the drive. Otherwise, if it is an old Mac with a real HDD, then you can open it, pull the drive, and erase it if you have the proper hardware to hook it up as an external drive. Or, just remove it, recycle the Mac, and throw the HDD in a junk drawer.

    Jeff
    3 years ago

    Perhaps I was not clear. The person i got the Mac from obviously didn’t clear out everything. i want to upgrade to Sierra and it is showing the former owner’s Apple ID. Is your video instructions what I should do so I can upgrade?

    3 years ago

    Jeff: So it sounds like the person cleaned off the Mac, but then made the mistake of re-installing the OS using their Apple ID, instead of what I show in this video. I think you can use the technique I show in the next video (https://macmost.com/reinstall-macos.html) to install Sierra over Sierra, but with your Apple ID. I would definitely backup beforehand and don’t choose to erase the drive (unless you have nothing on it anyway). But I’ve never tried to fix this particular issue in this way, so I can’t be sure it will work.
    If you live close to an Apple Store, it may be worth a visit to the Genius Bar.

    Doris McDermott
    3 years ago

    Your videos are helpful to many people, but I am an 89 year old who does well with printed instructions. I am sorry printed instructions are not available for all your courses.

    3 years ago

    Doris: There is a transcript if you would rather read that. But I understand what you are saying. I would look at the computer books available (Amazon or your local store) and maybe find a good Mac book or two.

    Dinesh Taylor
    3 years ago

    Hi Gary – I have an older MacBook – Model Identifier MacBook 4,1 with a Boot Rom Version: MB41.00C1.B00. I want to clean this laptop up and give it to my grandkid. I Option, Command, R does not restart the machine in the internet recovery mode. I also checked the site for updating the firmware at About EFI and SMC firmware updates for Intel-based Mac computers but no luck. Any suggestions to restart in internet recovery mode? I always look forward to your posts on Thursdays. Thanks

    3 years ago

    Dinesh: For older MacBooks like that, you need to do it the old way: insert the original DVD that came with it and boot from that. Then erase, reinstall the OS, and upgrade from there. I think you can also use a Snow Leopard install disk to do this, but you’d have to look up information specific to that Mac to know for sure — or just try it. Genius Bar if you can’t figure it out.

    Nassar
    3 years ago

    Great video sir although I wished you would of explained the “Security options” when erasing a Disk. One of my cousins would want to sell his MacBook Pro that came with Lion 10.7 should he use this way? I mean the next buyer wants the latest macOS which the Mac is capable of running. Why use this over booting from recovery disk instead? I mean upgrading from Lion 10.7 to Sierra 10.12.1 would need alot of GB’s to download, plus an Apple ID which we dont want the next buyer to know?

    Dinesh Taylor
    3 years ago

    Gary – you are brilliant! I could not find the original DVD however I had the Snow Leopard disk and I tried and it worked. Thank you for your help. Dinesh

    3 years ago

    Nassar: Right, you don’t want to “purchase” (for free) the OS using your Apple ID. You want him to do it. So he gets to use his ID to purchase and install OS X. And for security options, only if you have a HDD (hard disk). Then go ahead and use the security options which will overwrite the bits.

    Susan Bautista
    3 years ago

    Hi, could I use this for iMac 2009?
    Please help ,thank you.

    3 years ago

    Susan: If your Mac is old enough to have an optical drive, then you probably need to boot with the disc that came with the machine, or a Snow Leopard disc, and do it that way.

    Yvonne Strugnell
    3 years ago

    HELP Help
    Cleaned everything off, except WiFi, and pressed Option, Command, R. Came up in Recovery Mode so went away for an hour or so as you suggested. Returned to find grey screen with black Apple logo and it’s been like that for a couple of hours. What do I do, please?

    3 years ago

    Yvonne: Wait a bit, especially if you have a slow-medium Internet connection. It needs to run OS X/macOS from an Internet-based drive. So it could take a while. I think it took 20 minutes for me, and I have a very fast connection.

    Yvonne Strugnell
    3 years ago

    Gary, I think that 2 hours is rather long and I can hear no disc activity. I’ve managed to reinstall Mavericks, which it was running, but it’s all still registered to me. As I’m selling the iMac I need to reset etc for the new owner. Had a thought, in your video tutorial you imply that the OS that will be installed is the one that came with the Mac -I think it originally came with Snow Leopard and I’ve got those discs. Should I try to reset using those instead of trying the method above?

    3 years ago

    If this is an old Mac — old enough to have an optical drive, then yes, just use Snow Leopard discs and install from those. And be sure to include those in the sale.

    Yvonne Strugnell
    3 years ago

    Well, I tried it and it worked so now the new owner can start from fresh and upgrade to Sierra if he wants.

    Jose
    2 years ago

    I did everything that I follow on your video but my mac but it stop with a pic of the world with a “! ” This sign in the center and it says apple.com/support 501OF can you please tell Me what I need to do next ? Thank you.

    2 years ago

    Jose: seek the firsthand help of an expert. Genius Bar or local shop.

Comments Closed.