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MBX

macrumors 68020
Original poster
Sep 14, 2006
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816
Hi there

I'm a bit paranoid as I'm about to sell my previous/ old MBP and I erased the disk in CMD-R mode.

However is it possible for somebody to recover all my files with some recovery tools if they wanted to?
 

iMacDragon

macrumors 68020
Oct 18, 2008
2,311
671
UK
Don't worry. It will be permanently gone. No one can recover the files.

That depends what erase options were selected, if it only took seconds, unless it's a 2018 model, it would not have been a true erase. Need to set the 'security options' on disk utility erase disk to the second notch and overwrite with 0's to ensure nothing can be recovered.
 
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MBX

macrumors 68020
Original poster
Sep 14, 2006
2,030
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That depends what erase options were selected, if it only took seconds, unless it's a 2018 model, it would not have been a true erase. Need to set the 'security options' on disk utility erase disk to the second notch and overwrite with 0's to ensure nothing can be recovered.

It's a late 2016 model. There were not many options to select from. APFS and APFS (encrypted) and some other two. I remember there used to be an option to select what kind of erase security level to choose from but seems gone.
 

maflynn

macrumors Haswell
May 3, 2009
73,307
43,129
I wouldn't worry about recovery. Even back when using spinning hard drives and the risk of recovering the data was a lot higher. The cost of doing so after a erasure and reinstall made it unlikely that the common thief would undertake such an operation. With SSDs the information is effectively gone, I wouldn't worry.
 
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MBX

macrumors 68020
Original poster
Sep 14, 2006
2,030
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I wouldn't worry about recovery. Even back when using spinning hard drives and the risk of recovering the data was a lot higher. The cost of doing so after a erasure and reinstall made it unlikely that the common thief would undertake such an operation. With SSDs the information is effectively gone, I wouldn't worry.

My concern is that if I sell my MBP to a Apple certified (third party) store that they may dissect everything and try a data recovery. Not sure if they really would do it but I know they offer data recovery services and I'm a bit paranoid that they may try to do it on people's disks.

Are you sure about SSD's data "effectively gone" when you do a simple disk erase via CMD-R installation?
 

maflynn

macrumors Haswell
May 3, 2009
73,307
43,129
store that they may dissect everything and try a data recovery. Not sure if they really would do it but I know they offer data recovery services and I'm a bit paranoid that they may try to do it on people's disks.
Do you think it will be profitable for them to spend thousands upon thousands to pay for data recovery and what will they get in return? If we're talking about the Tim Cooks, Bill Gates of the world, or something then maybe but for simple consumers, there's really no incentive to spend all of that money for what will be nothing much in return.

Also will an apple certified company risk dealing with police and losing accreditation, along with spend a boat load of cash to pay for the data recovery?
 
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MBX

macrumors 68020
Original poster
Sep 14, 2006
2,030
816
Do you think it will be profitable for them to spend thousands upon thousands to pay for data recovery and what will they get in return? If we're talking about the Tim Cooks, Bill Gates of the world, or something then maybe but for simple consumers, there's really no incentive to spend all of that money for what will be nothing much in return.

Also will an apple certified company risk dealing with police and losing accreditation, along with spend a boat load of cash to pay for the data recovery?

I'm not talking about costly data recovery of damaged disks.

Aren't there apps for like under $100 bucks that can recover files from non-damaged disks (that are just erased manually) very well?

Maybe I'm too paranoid.
 

maflynn

macrumors Haswell
May 3, 2009
73,307
43,129
Aren't there apps for like under $100 bucks that can recover files from non-damaged disks (that are just erased manually) very well?
Can those recover SSD data that was erased (And/or encrypted)?
 

deeddawg

macrumors G5
Jun 14, 2010
12,223
6,350
US
My concern is that if I sell my MBP to a Apple certified (third party) store that they may dissect everything and try a data recovery.
What on Earth are you into that would make that effort/expense worthwhile?
 

Fishrrman

macrumors Penryn
Feb 20, 2009
28,105
12,255
"My concern is that if I sell my MBP to a Apple certified (third party) store that they may dissect everything and try a data recovery..."

I wouldn't spend too much time worryin' about it... ;)

Song lyrics for ya:
https://www.azlyrics.com/lyrics/crosbystillsnash/forwhatitsworth.html

Paranoia strikes deep
Into your life it will creep
It starts when you're always afraid
Step outta line the men come and shoot you down
 

deeddawg

macrumors G5
Jun 14, 2010
12,223
6,350
US
Aren't there apps for like under $100 bucks that can recover files from non-damaged disks (that are just erased manually) very well?

Maybe I'm too paranoid.

There are apps which can read data directly from HDD sectors after someone did a simple "delete" which merely marks the sectors as available for overwriting when new data needs to be stored.

Which is why you do an overwrite style erase on HDDs. Then you're talking disassembly and specialized equipment to try to find the underlying residual magnetization to reconstruct the data.

SSDs are a bit trickier for various reasons. Personally though, if the SSD is encrypted with a strong key and then reformatted it's going to be extremely difficult/costly/time-consuming to recreate anything.

Folks *are* encrypting their systems, right? We all know that's the smart thing to be doing anyway, right?
 
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MBX

macrumors 68020
Original poster
Sep 14, 2006
2,030
816
There are apps which can read data directly from HDD sectors after someone did a simple "delete" which merely marks the sectors as available for overwriting when new data needs to be stored.

Which is why you do an overwrite style erase on HDDs. Then you're talking disassembly and specialized equipment to try to find the underlying residual magnetization to reconstruct the data.

SSDs are a bit trickier for various reasons. Personally though, if the SSD is encrypted with a strong key and then reformatted it's going to be extremely difficult/costly/time-consuming to recreate anything.

Folks *are* encrypting their systems, right? We all know that's the smart thing to be doing anyway, right?

If by encrypting you mean FileVault, no thanks.

I've had huge issues with it in the past all the times. It slowed down the system and even corrupted files and disks. Maybe not anymore the case but I'm too hesitant to trust it.
 

deeddawg

macrumors G5
Jun 14, 2010
12,223
6,350
US
If by encrypting you mean FileVault, no thanks.

I've had huge issues with it in the past all the times. It slowed down the system and even corrupted files and disks. Maybe not anymore the case but I'm too hesitant to trust it.
That's the cool thing with technology. Stuff improves and advances, such as with putting the encryption engine in hardware in the T2 chip so there's no performance impact. Though to be honest I've never had any issue or perceived performance impact on either my 2012 mac mini or 2015 RMB12. Don't remember any issues or impacts with my old 2010 MBP13 either, but that's just my experience. Our corporate policy forces encryption on all our ~300-ish macs and has for years, haven't heard any issue there either. Not saying you didn't have some issue in the past, but it's pretty solid in everything I've seen.

But if you wish to walk around with all your stuff unprotected in the event of your laptop being stolen, that's certainly your call.
 

maflynn

macrumors Haswell
May 3, 2009
73,307
43,129
I've had huge issues with it in the past all the times. It slowed down the system and even corrupted files and disks. Maybe not anymore the case but I'm too hesitant to trust it.
What an odd comment.

I mean you seem very conscience of risking your data, but are unwilling to encrypt your data? That doesn't make sense at all. If you're worried about people stealing your data, then don't sell your Mac.

Just to point out the summary of the thread:
1. The risk is low regarding Apple certified dealers.
2. You can mitigate the risk incredibly by protecting your data, i.e., encrypting it.

If you don't feel comfortable with both, then you probably shouldn't sell your laptop

Btw, I've been running FileVault on my 2012 rMBP for many many years problem free.
 

NoBoMac

Moderator
Staff member
Jul 1, 2014
5,625
4,185
Just do what Audit13 and others are suggesting. Since getting rid of the Mac, turn on encryption, erase, re-install. Or erase, install with encryption on, erase, re-install. Either way, since the machine will no longer be yours, no need to worry about "issues" with encryption. And whatever data was written to the drive will no longer be readable since the original encryption randomly generated key(s) will be erased.

And yes, odd that concerned about file security, but not willing to turn on encryption for the drive.
 

PhilMacbook

macrumors regular
Mar 16, 2018
185
219
Britain
What on Earth are you into that would make that effort/expense worthwhile?

He might simply be worried about having bank account information on there or anything that could be used for ID fraud. I think he has a reasonable concern and most people take their data security too lightly these days, which is why ID fraud happens so often.

I don't know how he can erase the drive so data can't be recovered but I think he is right to want to.
 

deeddawg

macrumors G5
Jun 14, 2010
12,223
6,350
US
He might simply be worried about having bank account information on there or anything that could be used for ID fraud. I think he has a reasonable concern and most people take their data security too lightly these days, which is why ID fraud happens so often.

I agree folks should take reasonable precautions. Such as storing their sensitive info in an encrypted manner such as using 1Password to store info rather than typing it into plain text files.

He referenced "dissecting everything" suggesting a concerted effect to dig through unlinked data blocks attempting to recreate something. That's a lot of time an effort for low reward, and thus rather improbable other than instances where the person at the store might have reason to think there'd be a big jackpot.

I don't know how he can erase the drive so data can't be recovered but I think he is right to want to.

Google is a pretty cool tool. One of the top links to a search on "how to secure erase macbook pro ssd" is this: https://www.backblaze.com/blog/how-to-wipe-a-mac-hard-drive/

The question is moot if the person is using an encrypted drive to begin with; all data would be encrypted already so there'd be nothing to snoop through.

FAR higher probability of someone stealing the laptop and looking through for usable information than a reputable used-computer wholesaler risking their entire business.

Years ago whole-disk-encryption did impose enough of a penalty that folks needed to think through whether it was worth the performance impact to gain that security. These days though the performance impact is relatively small -- and with the new T2 chips it's effectively non-existent.
 
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deeddawg

macrumors G5
Jun 14, 2010
12,223
6,350
US
Unfortunately Apple no longer offers "security level" option in the erase section of disk utility.

Correct.... I'm puzzled at your response though. :confused: o_O

The linked article specifically mentions that, discusses the matter, and then provides a couple options. Including a way to securely erase freespace on your internal SSD despite Disk Utility.

That's why I linked the article.
 

Fishrrman

macrumors Penryn
Feb 20, 2009
28,105
12,255
Perhaps it's worth noting that even though Disk Utility may no longer offer a "secure erase" option for SSDs, apps like Drive Genius and TechTool Pro still do...
 

Sackofnickels

Suspended
Jul 13, 2018
285
492
A secure erase writes over the old data multiple times. Just erasing, or reformatting does not do it. On the other hand I wonder if that idea still applies to SSD's?
 
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