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Wiping iMac drive for trade-in.
- Thread starter cmcbhi
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Use Disk Utility to erase an Intel-based Mac - Apple Support
How to erase (format) the built-in startup disk of an Intel-based Mac.
It wipes it all, but it might be still possible to recover it.
If you are that worried about it, do the highest level of secure erase. I think the highest level overwrites the data 35 times.
Just keep in mind that the higher levels of secure erase could take a very long time to finish.
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It is possible under certain conditions, depending on the OS, how it is connect to the computer (like Internally or external TB or USB), if TRIM was enabled.
But the OP is using a Fusion Drive, and assuming that it isn't a custom Fusion Drive of all SSDs, there is a HDD. The data on the HDD could be recovered.
Most likely no one would care to recover the data, but if the OP is that concerned about it, then the OP should do a secure erase. I think Apple may have removed the secure delete from the Disk Utility a few OS versions ago, but I always keep old bootable OS partitions just to use old versions of Disk Utility.
Another option that might work is to to encrypt the Fusion Drive, then wipe the drive by reformatting it unencrypted when. I assume that this may take even more time than zeroing the data a few times.
Screenshot of most secure erase below.
The only keyboard I have for the iMac is the original bluetooth.
I the past, I have had difficulty accessing recovery, etc by using this keyboard.
Do I need a hardwired keyboard (USB, etc to access the recovery option?
Would this erase be safe enough?
The only keyboard I have for the iMac is the original bluetooth.
I the past, I have had difficulty accessing recovery, etc by using this keyboard.
Do I need a hardwired keyboard (USB, etc to access the recovery option?
Would this erase be safe enough?
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What version of MacOS are you using? I thought that Apple removed the GUI for Secure Erase from Disk Utility on newer OS versions.
But... I notice that it only goes up to 7 passes. Apple removed the higher pass options.
Still, I am sure that 7 passes is overkill for consumers.
If you are worried about getting into recovery mode to reinstall the OS, you can install the OS on an external drive, thumb drive, SD card, etc. and use that to boot from. Secure delete the Fusion Drive all while booting from the external.
Then run the installer again within the external boot drive.
Reinstall then do the trade.
The more passes, the more time consuming it would be to recover data.
On your version of disk utility secure delete only goes up to 7 passes, it used to be 35 passes. I suspect that it was dropped to 7 due to the amount of time to complete the 35 passes.
If you are that concern about your data being recovered, you should physically destroy your HDD. If you are not sure how, I am sure there are plenty of YouTube videos explaining best practices.
But... I notice that it only goes up to 7 passes. Apple removed the higher pass options.
Still, I am sure that 7 passes is overkill for consumers.
I haven't use BT Keyboards in a long time, so I don't know.
If you are worried about getting into recovery mode to reinstall the OS, you can install the OS on an external drive, thumb drive, SD card, etc. and use that to boot from. Secure delete the Fusion Drive all while booting from the external.
Then run the installer again within the external boot drive.
Reinstall then do the trade.
It isn't a guarantee that data cannot be accessed.
The more passes, the more time consuming it would be to recover data.
On your version of disk utility secure delete only goes up to 7 passes, it used to be 35 passes. I suspect that it was dropped to 7 due to the amount of time to complete the 35 passes.
If you are that concern about your data being recovered, you should physically destroy your HDD. If you are not sure how, I am sure there are plenty of YouTube videos explaining best practices.
Catalina 10.15.6
If my late 2013 iMac could run Big Sur I might not trade.
Well, 7 years is the most I've ever kept a single machine, so I probably would.
Previously, I had built (assembled the bits) Windows machines, but when I got this iMac, I was reformed.
I just want to make sure my passcodes and other data is securely erased. Previously, I just pulled the disks and used a sledge hammer.
As an aside, ant pros/cons about using Time Machine versus migration assistant versus Carbonite to transfer data? Both machines have the same version of Catalina.
I'll start the erase/trade process when the new machine arrives.
Many thanks.
If my late 2013 iMac could run Big Sur I might not trade.
Well, 7 years is the most I've ever kept a single machine, so I probably would.
Previously, I had built (assembled the bits) Windows machines, but when I got this iMac, I was reformed.
I just want to make sure my passcodes and other data is securely erased. Previously, I just pulled the disks and used a sledge hammer.
As an aside, ant pros/cons about using Time Machine versus migration assistant versus Carbonite to transfer data? Both machines have the same version of Catalina.
I'll start the erase/trade process when the new machine arrives.
Many thanks.
My understanding was that with Fusion formatted drives, you have to defuse the drive, secure wipe and then refuse the drive? Which sounds like too much effort if I am honest.
I tried the 'secure security options' kept getting an error message please use 'filevault' something along those lines.
I tried the 'secure security options' kept getting an error message please use 'filevault' something along those lines.
I'm not advocating that you be super paranoid, but if you're concerned that drive erase "may not be enough", then just open up the iMac and remove the drive itself.
Can anyone tell me why this wouldn't work:
To me, this would be the easiest, and simplest solution to protect from data recovery. It also doesn't require opening the Mac or special SW. Everything built right into the OS.
To me, this would be the easiest, and simplest solution to protect from data recovery. It also doesn't require opening the Mac or special SW. Everything built right into the OS.
Who are you trading in the computer to? Your level of paranoid-ness goes down if you are turning it into Apple versus some "We'll give you $50 for it!" reseller on the internet.
The only way to absolutely, 100% ensure that the data cannot be recovered is to put a bullet in it. Really, the Government DESTROYS hard drives when they want to ensure no one can access it ever again. All the other options just make it much much harder to do.
Keep in mind, if you've ever had a hard drive fail on you and then tried to recover the data... it's not that successful. No one is really going to spend that much effort to recover data from a hard drive unless there is something they really want from it. You have the credit line of Tim Cook? Have something stored on your hard drive worthy of putting you in prison? Old family photos worthy of memes if put on the internet?
Most people have already put more sensitive information about themselves than you can shake a stick at merely by having any online presence at all. If you have to log in to a site, someone else besides you has your credentials already. Pretty much everything about you sits out there in the nether of the world wide web... waiting to be accessed by some clever kid with too much time on their hands.
The only way to absolutely, 100% ensure that the data cannot be recovered is to put a bullet in it. Really, the Government DESTROYS hard drives when they want to ensure no one can access it ever again. All the other options just make it much much harder to do.
Keep in mind, if you've ever had a hard drive fail on you and then tried to recover the data... it's not that successful. No one is really going to spend that much effort to recover data from a hard drive unless there is something they really want from it. You have the credit line of Tim Cook? Have something stored on your hard drive worthy of putting you in prison? Old family photos worthy of memes if put on the internet?
Most people have already put more sensitive information about themselves than you can shake a stick at merely by having any online presence at all. If you have to log in to a site, someone else besides you has your credentials already. Pretty much everything about you sits out there in the nether of the world wide web... waiting to be accessed by some clever kid with too much time on their hands.
This is true.
This reminds me of when I was working for a federal contractor processing personal effects of wounded and fallen service members as well as some other government agencies and contractors.
One part of the process was called "media center", and involved scanning various types of media for classified material and data, as well as pornography and other sensitive material.
I worked in the media center, and we looked at everything, Macs, PCs, iPods, Zunes, SD cards, DVDs, CDs, smart phones, dumb phones, camera, magnetic tapes, HDDs, etc. Pretty much anything and everything with analog or digital data, we looked through it.
Getting to the point, almost every PC (that worked) was easy to obtain all the data. Occasionally, there was something encrypted, and we had software to crack it. If it was unsuccessful, or appeared to be taking forever, we would then send it to the FBI, which had like a month or two turnover time, and I have never seen a PC that the FBI wasn't able to crack.
I was the Mac guy, so I handled most of the Apple stuff, and it was pretty easy to get data off of them as well.
But, if something had File Vault, there was nothing we could do. We were sending them to the FBI, but the FBI told us to stop sending a Mac with File Vault. Either the FBI couldn't crack it, or the time and resources involved too much for the FBI to spare.
Basically, we would spend days attempting to guess the password, brute force style. We would ask the families for guesses of what the password might be. Most remained locked, and we would end up just destroying the drives.
So, getting to the point for the OP, if you are that worried about it, encrypt the data then format the drive. This is basically a hard stop for most people trying to access the data.
If you are worried about the .000001% of people that have the time, know how, and a need to access your data, then you shouldn't be trading the computer into Apple and the drive should be destroyed.
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