I thought I erased everything the other day, went through disc utility and erased, it took quite a long time to finish, thought it seemed OK. But there is still all kinds of data on the computer, pictures, emails, everything. So I tried to erase again. Went to disc utility, clicked on Macintosh HD, but I cannot Erase, the table is not bolded as an option. Just First Aid or Partition. (BTW, this is true in both “Wipe”, the user you had you me create, and under our own log in user id). If I go to “Show all devices” and drill in, I can get APPLE HDD HTbunch of numbers drive and this I CAN erase. But is this what I want to do? Not sure. (BTW, sending it back to Apple for money back.)

Sorry, this seems so easy, wish I didn’t have to bug you. Thanks so much.


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If all you're trying to do is just wipe the computer to send it back to Apple then you can take an even easier path by booting into Recover mode and wiping the drive from there. The reason you cannot erase the drive from disk utility in the manner you are attempting in the pics above is because the computer cannot erase the operating system it's currently booted into. It would be sort of like computer suicide. So the work around on that is recovery mode.

Boot the computer holding down command+r and you'll boot into an unfamiliar screen.



From there, choose disk utility but this time you WILL be able to erase the main drive. Once this is done, the computer will not be able to boot into an operating system. That's ok though because Apple would just be wiping it anyway. While it is always a good idea to consider the data on your computer, Apple doesn't care about your data. They will wipe the drive again (and even run zeros and ones over it) before they ever repurpose the machine anyway.

That's the easiest way to do it. If you were going to be donating this computer to someone then we would look at the erase differently. This is the nuclear option and is fine if you're just sending it back to Apple.