HD now working after writing ZEROS

[beavereater]

In my earlier posts I wrote about how my 1.5T WD hard-drive was causing my system to crash. I downloaded the diagnostic software and it wouldn't pass the S.M.A.R.T scan (Failed). Once I got my new drive (This is before shipping off the old one to be replaced under warranty) I had to move as much data as I could from my HD. It took a couple tries to get the system to stay on long enough to move all my data over.

Once that was done, I used the same software to 'write zeros' and format the drive, which took about 7 hours. I thought that if I was sending this off, I didn't want any possibility of my data remaining on the drive. The drive actually stayed on the whole 7 hours.

I then decided to re-check the drive. Not only did it pass the S.M.A.R.T scan but it also passed the 'Long scan'.

Now, I'm not an expert so I don't know why this would be. Should I still send this in? Would WD actually be checking the drive and finding that it does work (Now that I've formatted it)? Or are there still bad sectors that just aren't being seen? I really don't know.

I do still have the log file for the drive of the diagnostic scan...but any input would be great!

[SLK001]

SMART keeps the high and low values, so if it failed once, there should be a record of it stored on the drive. If I had seen a failure on one of my in-warranty drives, I would send it back.

[roma_turok]

Can you post screenshot SMART from HDDScan?
but remove serial from screenshot:

[jman98]

I agree with SLK001.

You need to understand that while writing zeroes is maybe effective against the vast majority of people, there are people in the world smart enough to still get your data. Writing zeroes, even multiple times, does not prevent the very best recovery experts from still getting your data. Universities have published papers that show that by using tools well beyond what any normal person would have that it is still possible to get back your data. No doubt various governments can do this too. I'm not suggesting that worrying about this is worthwhile but a lot of people have the false idea that they can overwrite their drives with ones or zeroes a few times and it can never, ever be recovered and that's not true for the very best experts.

[Cornucopia]

Yeah, but this isn't Osama Bin Laden's, John Lech Johanson's or even Ethan Hunt's or Jack Bauer's hard drive we're talking about here. It is just a dude who bought a HDD and is returning it under warranty. Ok, maybe he stored porn on it that he didn't want his family to know about, but I don't see the feds or even the manufacturers doing a "Level 3 Scrub" on this thing.

Scott

[Cornucopia]

Yeah, but this isn't Osama Bin Laden's, John Lech Johanson's or even Ethan Hunt's or Jack Bauer's hard drive we're talking about here. It is just a dude who bought a HDD and is returning it under warranty. Ok, maybe he stored porn on it that he didn't want his family to know about, but I don't see the feds or even the manufacturers doing a "Level 3 Scrub" on this thing.

Scott

[jman98]

Cornucopia - Sure. I just want him to understand that while it is unlikely, writing once to his drive is not sufficient to guarantee that nobody can ever get back his data. I'm not suggesting it's likely that anyone at the disk plant would care enough to try or even could, but a lot of people think "I wrote zeroes or ones to my drive and NOBODY can EVER get anything off of it" and that's not true.

[Cornucopia]

I agree. I was just thinking that the OP was more worried about the mfctr not believing anything was wrong with the drive rather than if they'd snoop for his/her personal stuff.

Scott

[AlanHK]

Cornucopia - Sure. I just want him to understand that while it is unlikely, writing once to his drive is not sufficient to guarantee that nobody can ever get back his data. I'm not suggesting it's likely that anyone at the disk plant would care enough to try or even could, but a lot of people think "I wrote zeroes or ones to my drive and NOBODY can EVER get anything off of it" and that's not true.

Actually, no one has ever demonstrated they can recover files from a zeroed disk IN PRACTICE, beyond a few sectors. Theoretically possible, maybe the CIA has a special secret lab that can, but anyone else, anyone at the disk plant, no.

I'm sure I won't change your mind, but I'm confident you can't prove that this has ever been done.

Anyway, back on the actual topic, I had a few problems with my PC recently. First the power supply literally exploded. I replaced it, it seemed to boot okay and ran for a few days, but got increasingly unstable. I thought the hard disk might have been damaged, it was pretty old anyway, so I bought a new one and got it running again. But that also started to crash. I ran some tests on it using GSmartControl on the PartedMagic bootable CD (using another PC). That told me there were some bad sectors on the disk, which really pissed me off as it was new. But I cooled down and copied my files off it, and then used another app on the CD (can't recall the name, possibly Nwipe) to give it a low level format -- i.e. writing zeroes throughout.

Aside from erasing the data and file structure, this also removes the bad sector marks. Then I used GSmartControl again and ran several complete surface tests. No bad sectors. So I'm pretty sure that my original mobo was flaky, the IDE controller perhaps, and that the disk itself had no hardware problems, it just had bad data written to it. I've been using the disk for a few months now, every now and then running a complete test, but it has remained error free.

So the moral is, bad sectors may not mean a bad disk and possibly (not always, of course) can be repaired by a low level format. And they can indicate problems elsewhere in the PC -- cables, power, motherboard.

[jman98]

AlanHK - Kinda late to the party, huh?

I refer you to this.
http://www.techrepublic.com/blog/datacenter/think-youve-wiped-that-hard-drive-think-again/272

I'm not saying it's practical and I'm not suggesting at all that the equipment to do this is readily available, but I think it is possible. The research that gets published about it is from work done at American universities. Slashdot has posted articles about this in recent years.

I've said all I'm going to say on this subject here as we're starting to hijack this thread by continuing to debate it. But if you want to rebut my post, you can have the last word.

[AlanHK]

AlanHK - Kinda late to the party, huh?

I refer you to this.
http://www.techrepublic.com/blog/datacenter/think-youve-wiped-that-hard-drive-think-again/272

I'm not saying it's practical and I'm not suggesting at all that the equipment to do this is readily available, but I think it is possible. The research that gets published about it is from work done at American universities. Slashdot has posted articles about this in recent years.

I've said all I'm going to say on this subject here as we're starting to hijack this thread by continuing to debate it. But if you want to rebut my post, you can have the last word.

I love it when someone tries to have the last word in a thread by implying that the other person is the one who insists on having it.

Anyway, looking at your reference, most of it is about people who just "deleted" files, not overwriting them, just unlinking them. Any idiot can recover those.

Other than that, the only scientific reference is from an article written in 1996. Hard disk technology and densities have gone up by orders of magnitude since then. And still, that was NEVER PUT INTO PRACTICE. As the authors say:

Looking at this from the other point of view, with the ever-increasing data density on disk platters and a corresponding reduction in feature size and use of exotic techniques to record data on the medium, it's unlikely that anything can be recovered from any recent drive except perhaps a single level via basic error-cancelling techniques. In particular the drives in use at the time that this paper was originally written are long since extinct, so the methods that applied specifically to the older, lower-density technology don't apply any more. Conversely, with modern high-density drives, even if you've got 10KB of sensitive data on a drive and can't erase it with 100% certainty, the chances of an adversary being able to find the erased traces of that 10KB in 200GB of other erased traces are close to zero.

No one has ever demonstrated they could recover a single file.

[bendixG15]

Routinely being able to retrieve data from zeroed drives kinda reminds me of that guy .... Don Quixote attacking the windmills

[Moontrash]

You can search newegg or amazon and there are reviews/comments scattered around and you'll notice that some mention that they have received replacement drives and those drives had previous data on them from other users....i.e...they were getting redone/refurbed drives. There are even more comments on usb thumb drives like that with previous users data still on em. This shows that these hdd companies aren't too efficient on deleting or getting rid of previous data on returned hdd's. Just wipe the drive with between 3 or 7 pass (Eraser wiper works well) and send it back...you'll be fine.

The problem with that article is that they give you zero info about the hdd's. They say they got a 50% recovery of data rate from hdd's they got on ebay or elsewhere. Problem is, they have no info about the wipe or delete procedure on the drives. That's not very helpful. If they got a hold of 100 hdd's and threw a myriad of data on them and they took 50 and wiped them from 3 to 7 times and the other 50 they just "deleted" or formatted em then I would say it's a insightful article. They haven't done either. By pulling data from 50% of the drives they had they just proved they did just that...pulled data off of the drives. That's not enough proof they can do it to almost any drive. How was the data delted or gotten rid of to begin with?

I was reading a few articles last year on this very subject. I stumbled onto them from somewhere and for the life of me I can't remember what the links are but they are in line with what AlanHK has mentioned. No less than a 3 pass wipe on a hdd and you'll survive. Just don't "format" or "delete" the data and expect to be safe. That's not effective enough.

[aedipuss]

the only successful data retrieval of a 0'd or wiped drive was done in an academic setting using an magnetic force microscope to look under each magnetic particle to find it's previous state. anyone want to guess how many magnetic particles are on a current sized hard drive..... if the world were going to end if a drive wasn't recovered it might happen before the sun burned out.

anything more than a 1 pass wipe is only to placate a guilty conscious.

[AlanHK]

The problem with that article is that they give you zero info about the hdd's. They say they got a 50% recovery of data rate from hdd's they got on ebay or elsewhere. Problem is, they have no info about the wipe or delete procedure on the drives. That's not very helpful. If they got a hold of 100 hdd's and threw a myriad of data on them and they took 50 and wiped them from 3 to 7 times and the other 50 they just "deleted" or formatted em then I would say it's a insightful article. They haven't done either. By pulling data from 50% of the drives they had they just proved they did just that...pulled data off of the drives. That's not enough proof they can do it to almost any drive. How was the data delted or gotten rid of to begin with?

Very likely, no one bothered to even try to delete it.
I've picked up computers in the trash and scavenged parts, found the hard disk completely intact, including emails, resumes, etc, etc.
Same with a junked mobile phone, had hundreds of SMS in its memory.

Recently I bought a used hard disk, it was full of TV shows, obviously from a hard disk recorder.

The dealers who sell these don't care, and why should they if the original owners didn't; they probably just get a job lot of old PCs and strip out the drives and RAM and put them up for sale. They don't even need to test them, they can offer a guarantee and let the buyer test them, or just make it "as-is" and shrug if it doesn't work.

[aedipuss]

i personally use the 20lb. sledgehammer method before throwing out failed hard drives.