Erasing a Windows PC HDD

[PrinceAvalon]

Hey all,

I'm selling one of my old Windows machines to my cousin. He is straight but he knows a lot of shady people and I do online banking and shopping so I'm aware it's very wise to erase a HDD. I bought Killdisk and was wondering what method is good to pretty much guarantee nothing will be able to be obtained and reconstructed somehow?

I tried 2 other tech forums and no answer yet and they're a few weeks old so figured this is my last place to get suggestions.

 

[spinnerlys]

If you have a Mac (I assume, as you post this in a Mac forum) you still might have your gray restore DVDs.

Boot from the first via holding down C during booting, then select a language, then go to Utilities > Disk Utility in the Menu Bar, select the HDD you want to erase, click on Security Options and select Zero Out Data. That will overwrite all the data on the HDD with zeros, something only professionals with hardware equipment might be able to restore.

Also have a look at MRoogle, as that question is asked a lot.

 

[PrinceAvalon]

If you have a Mac (I assume, as you post this in a Mac forum) you still might have your gray restore DVDs.

Boot from the first via holding down C during booting, then select a language, then go to Utilities > Disk Utility in the Menu Bar, select the HDD you want to erase, click on Security Options and select Zero Out Data. That will overwrite all the data on the HDD with zeros, something only professionals with hardware equipment might be able to restore.

Also have a look at MRoogle, as that question is asked a lot.

Actually no, this particular machine is a PC. Even if this is a "Mac" board, someone on here realistically should know something about HDD erasure and/or used windows so might know/be able to suggest how many passes is fine.

Killdisk to my knowledge is for Windows only... maybe not. I have a Mac Pro now..... but... my old machine; I have a few OOPS, or one of them I'm selling to my cousin but I did some online stuff on that so it's best to erase it to be safe.

I heard a single pass with zero's though it technically erases it is very poor security wise and very easy to reconstruct the data that was on it. I tried two other tech forums; one of which I was a member of for a long while, and no replies yet so.....

Like I said in my original post.... no replies in about a month since my post.. but one has a few hundred reads really no one knows lol... on a tech/computer forum????

This is the last forum that I'm a member of related to computers to try.

If this is gonna cause an issue I guess I can just do a 7 or 10 pass but I'd rather not use that unless it's strongly suggested as it's a 1TB drive being erased so that'll take some time.

 

[spinnerlys]

Have a look at this thread: https://forums.macrumors.com/threads/840454/

Quote from there:

Guys, as a DoD employee and a computer forensics investigator, here is the lowdown... NOBODY has been able to recover any usable data from a drive that has even been single pass wiped. The DoD used to abide by the 3Pass wipe standard but has now adopted 7 pass. I've taken my GIAC certification and even in these classes NOBODY has been able to recover after a single pass has been made. The only reason why the DoD uses 7 is "in the event of future technological advancements", perhaps someone can figure it out years into the future. But for personal data, I would say that a single pass is going to pack enough stopping power for anyone that has the tools to recover deleted files. If you're trying to protect yourself because you've got something illegal on the drive, then ummm you should go ahead with the paranoid 35Pass. It will take a really long time, probably more than a full day at the least.

Oh yeah and if you keep the drive and decide to physically destroy it later...Well make sure you take it apart fully and scrape the platters down real good with a sander or wire brush. Some data recovery firms have been able to recover data off platter FRAGMENTS that were blown apart from an IED attack. Amazing technology out there.

I once tried to recover data from an HDD which was erased with one pass of zeros. I used Data Rescue, a 99USD software which saved me quite some times, and all I was able to recover was gibberish, no data I could use in any way besides looking at it dumbfounded.

I have no clue about this Windows software, as I, like many here, don't use that OS.

So if you have no problem using your Power Mac and connecting that HDD, either in an enclosure or via Target Disk Mode, you can use Disk Utility for free.

Unless this person you're selling that OOPS (whatever that is) to is a professional in data recovery, a single pass of zeros is enough.
Imagine a single pass of zeroing out data like a puzzle with one billion pieces, or even many more, where your original data was the image on all the pieces, and the zeroing out is painting every piece with a single colour, white for example, and dismantling the finished puzzle with all the pieces not connected to each other anymore and being put in a box, where those pieces form a chaotic pile.
Can you now imagine how much time it does take to put the puzzle together again, with only white pieces? Even removing the white from one billion pieces takes more time than one likes to take.

If you want to use Windows, have you taken a look at Control Panel > Administration > Computer Management > Disk Management and seen if it offers some kind of secure erase?

If you want help with Windows related questions, maybe you should add that to your title, as your OP and the thread title are not clear about that.

 

[PrinceAvalon]

Have a look at this thread: https://forums.macrumors.com/threads/840454/

Quote from there:




I once tried to recover data from an HDD which was erased with one pass of zeros. I used Data Rescue, a 99USD software which saved me quite some times, and all I was able to recover was gibberish, no data I could use in any way besides looking at it dumbfounded.

I have no clue about this Windows software, as I, like many here, don't use that OS.

So if you have no problem using your Power Mac and connecting that HDD, either in an enclosure or via Target Disk Mode, you can use Disk Utility for free.

Unless this person you're selling that OOPS (whatever that is) to is a professional in data recovery, a single pass of zeros is enough.
Imagine a single pass of zeroing out data like a puzzle with one billion pieces, or even many more, where your original data was the image on all the pieces, and the zeroing out is painting every piece with a single colour, white for example, and dismantling the finished puzzle with all the pieces not connected to each other anymore and being put in a box, where those pieces form a chaotic pile.
Can you now imagine how much time it does take to put the puzzle together again, with only white pieces? Even removing the white from one billion pieces takes more time than one likes to take.

If you want to use Windows, have you taken a look at Control Panel > Administration > Computer Management > Disk Management and seen if it offers some kind of secure erase?

If you want help with Windows related questions, maybe you should add that to your title, as your OP and the thread title are not clear about that.

Sorry... thanks for that advice. Oops is just a saying I caught from a friend I had for years and now I say it like breathing lol.

Personally, I don't have much experience in erasing hard disk's lol... just some used to tell me if you ever sell a machine to someone else erase the drive first... cause alot of criminals buy second hand computers hoping to find credit card numbers and such and bank info to play identity theft.

I use both Windows and a Mac now.... and didn't care to do the whole install it on the mac too but then I still had a Windows box I was using so I didn't need too.

Well the killdisk application has a 3 pass DoD method <-- U.S. dept of defense uses so I'm sure that's some type of secure; which I presume is security erase, and a 7 pass method.

I guess the guy I quoted who said one pass w/zero's being easy to reconstruct he's talking about someone using professional equipment and stuff.... not just some basic freeware or 50 app....

**EDIT**

Like I said... my cousin who is straight as in in legal issues... he doesn't break the law, but he knows shady people and I don't know details but knowing he knows quite a few people who break federal laws or have... I'd rather be safe than sorry and if wondering using a 3 or 7 pass was better.

 

[sushi]

Mac --> Disk Utilities works great.

PC --> KillDisk works great.

You can use either computer to wipe a HDD from either. For example, I can use KillDisk to erase my Mac's HDD. Just need to remove the Mac's HDD and attach it to a PC ... or vice versa.

As for security. One wipe is probably enough for most situations. However, my suggestion is wipe the HDD 2-3 times as a minimum if you have sensitive personnel data on it. You can do this directly from Disk Utilities on a Mac (Erase 7 times or select zero and do it three times manually) or by running KillDisk numerous times (the free version) or you can pay for it and run multiple erases.

Personally, I do 7 pass wipes for HDDs with personal data on it. Remember, once the HDD is out of your hands you no longer control what someone can do with it.

YMMV.

 

[PrinceAvalon]

Mac --> Disk Utilities works great.

PC --> KillDisk works great.

You can use either computer to wipe a HDD from either. For example, I can use KillDisk to erase my Mac's HDD. Just need to remove the Mac's HDD and attach it to a PC ... or vice versa.

As for security. One wipe is probably enough for most situations. However, my suggestion is wipe the HDD 2-3 times as a minimum if you have sensitive personnel data on it. You can do this directly from Disk Utilities on a Mac (Erase 7 times or select zero and do it three times manually) or by running KillDisk numerous times (the free version) or you can pay for it and run multiple erases.

Personally, I do 7 pass wipes for HDDs with personal data on it. Remember, once the HDD is out of your hands you no longer control what someone can do with it.

YMMV.

Yeah.. I have the paid for version of killdisk. Do you have any experience with it.... what is the custom.. does it just do "zero's" with however many passes you select.. and would 7 passes of that be better than the mixed method the 7 pass DoD or Air Force methods use?

What does YMMV mean OOPS sorry if that's a n00b question lol.

 

[OZMP]

disk utility + drive caddy or cheap external drive case (which ever you will get more use from)

 

[sushi]

Yeah.. I have the paid for version of killdisk.

I use the free version.

Do you have any experience with it.... what is the custom.. does it just do "zero's" with however many passes you select.. and would 7 passes of that be better than the mixed method the 7 pass DoD or Air Force methods use?

There are various ways to wipe the disc.

All zeros or ones multiple times. Or a pattern such as Zeros, Random, Zeros, Ones, Random, Zeros, Random.

Personally, I just use KillDisk multiple times to write zeros. And since I have the free version that will only do one wipe at a time, I just run it 2-3 times.

FYI, there are not ones and zeros written to a hard drive. Rather, magnetic particles are oriented in such a way that if a threshold is attained for a particular area of the hard disk, that area will read as a one. Anything below that will be read as a zero. That is why with sophisticated equipment, it is possible to reconstruct a hard drive after it has been erased by writing zeros to all locations.

Software such as SpinRite are great at conditioning hard drives for this very reason mentioned above.

What does YMMV mean OOPS sorry if that's a n00b question lol.

Your
Mileage
May
Vary

Just means your experience may not be the same as mine. Like a disclaimer.

 

[VaderMonkey]

I can recommend DBAN (Darik's Boot And Nuke). It's a good free utility I've used a few times.

http://www.dban.org/about

 

[JKitterman]

I would look at the Ultimate Boot CD and the HDDErase utility on it. It may be a lot faster if this is a more modern computer with a HD that supports these comands.
www.ultimatebootcd.com/index.html

 

[Chris Rogers]

disk utility + drive caddy or cheap external drive case (which ever you will get more use from)

Yeah, do this. Easiest way, + it takes less than 5 minutes.

 

[steve2112]

I can recommend DBAN (Darik's Boot And Nuke). It's a good free utility I've used a few times.

http://www.dban.org/about

Another vote for DBAN. It rocks. It does just as its name implies. Boot to the CD, and nuke the drive.

 

[PrinceAvalon]

I use the free version.


There are various ways to wipe the disc.

All zeros or ones multiple times. Or a pattern such as Zeros, Random, Zeros, Ones, Random, Zeros, Random.

Personally, I just use KillDisk multiple times to write zeros. And since I have the free version that will only do one wipe at a time, I just run it 2-3 times.

FYI, there are not ones and zeros written to a hard drive. Rather, magnetic particles are oriented in such a way that if a threshold is attained for a particular area of the hard disk, that area will read as a one. Anything below that will be read as a zero. That is why with sophisticated equipment, it is possible to reconstruct a hard drive after it has been erased by writing zeros to all locations.

Software such as SpinRite are great at conditioning hard drives for this very reason mentioned above.


Your
Mileage
May
Vary

Just means your experience may not be the same as mine. Like a disclaimer.

So no matter how many passes someone will be able to tell what was on it if they have the equipment.. what if I did the 35 pass method or just did a custom with 99 OOPS?

 

[steve2112]

So no matter how many passes someone will be able to tell what was on it if they have the equipment.. what if I did the 35 pass method or just did a custom with 99 OOPS?

That's overkill. A 3 pass will stop 95% of any attempts to recover anything. A 7 pass will prevent virtually any data recovery. I suppose theoretically, someone like Driver Savers could get their hands on the HDD platters and MAYBE recover something, but the likelyhood of that happening is next to nothing. I have used some forensic software designed to recover data, and have had little success with 7+ passes.

 

[sushi]

Just to throw out something here. With HDDs being so cheap these days, another method employed by some is to merely purchase a new HDD and put it into the computer after taking out the old HDD.

Then destroy the old HDD. Wipe the disk 7 times, then physically destroy it.

YMMV.

 

[steve2112]

Just to throw out something here. With HDDs being so cheap these days, another method employed by some is to merely purchase a new HDD and put it into the computer after taking out the old HDD.

Then destroy the old HDD. Wipe the disk 7 times, then physically destroy it.

YMMV.

Heh, we did that at a place I used to work. We would run the DOD diskwipe 7 pass on it, then "manually degauss" them with a 10 pound sledgehammer. It was a really good way to relieve stress.

 

[sushi]

Heh, we did that at a place I used to work. We would run the DOD diskwipe 7 pass on it, then "manually degauss" them with a 10 pound sledgehammer. It was a really good way to relieve stress.

I have one friend who loves to drill. After erasing his HDD, he takes a large metal drill and sees how many holes he can drill through the entire HDD. Funny.

Me, I just take them apart and play with the platters.

 

[steve2112]

I have one friend who loves to drill. After erasing his HDD, he takes a large metal drill and sees how many holes he can drill through the entire HDD. Funny.

Me, I just take them apart and play with the platters.

Yeah, the platters make pretty cube mirrors so you can see who is sneaking up on your cubicle. I personally like the magnets.

 

[sushi]

Yeah, the platters make pretty cube mirrors so you can see who is sneaking up on your cubicle.

Good use.

Sometimes, I toss them about like horseshoes.

Some of the 2.5 inch platters will shatter when you try to bend them.

I personally like the magnets.

Yep. They can bite you if you're not careful.

 

[atlanticza]

The DOS command Format c:\ should do the trick (but the OS will have to be reinstalled).

 

[sushi]

The DOS command Format c:\ should do the trick (but the OS will have to be reinstalled).

Actually, this does not work to erase the actual data on the HDD and leaves the existing data very easy to recover.

 

[PrinceAvalon]

I wasn't saying I was gonna do 35 passes lol... just wondering; since I'm not familiar with it, if even with forensic and professional stuff if stuff can still be recovered.. maybe I'm paranoid but I've had too many family screwed over financially for life.. due to identity theft....

My cousin is straight who I'm selling too as in he's never broken the law... and I would hope not since he wants to join the FBI one day but he's wanting to be a cop first....

Just he knows very shady people and as of now he is the highly suggestible type lol... so i was wondering how many passes will pretty much do it.... or should I just keep it as a spare for me... and just tell him he has to buy one? But I have 8TB in a NAS and 2 1TBs for basis storage and a 500 the OS and apps are on so it's not like I need the drive....

I wonder how fast an SSD would be... A friend claims a 10 pass he did took minutes..... I don't know if he was fudging facts... or if they erase that fast.... If that's the case you could do a friggin 99 pass and still finish before 1 pass on my 1TB