21 replies to this topic

[Cosmin]

I wish to sell my actual HDD (seagate barracuda 7200.10 200gb) and I need to erase permanently my personal (all) data.. which solution is recommended for my request?
thanks!

[XerXis]

full format.

If you want to be sure do it two times. If you really want to be sure use a program that writes random data to your disc. But in all honesty, the tales about data recovery are hugely blown out of proportion anyway. Nobody will be able to read any kind of residual data from your drive after doing a full format twice. And your data wouldn't be worth that kind of trouble and cost anyway (sorry )

[Princess Chica Ami]

Here is a solution for your problem.

http://www.pcworld.c..._hard_disk.html

There you go.

[lcg]

Although a full format should be fine as XerXis has explained, I would format the drive using DBAN if I was selling it. I'm a little paranoid.

[Cosmin]

And you recommend to erase partitions before that full format?

[Ambroos]

Just use DBAN and you're all set. It'll do everything to make your drive's contents 'as new'.

[+BudMan]

A full format in XP does nothing but remove the pointers and make sure the sectors can be read. This will not remove the ability to recover a file. If you are using vista or higher then it does write zero's and that would be good enough

As long as you write something over the sectors - then data can not be recovered. Doing multiple wipes is overkill, once is enough.

[MillionVoltss]

Ignore the comments regarding doing just a format, this is nonsense.

A format deletes where the information is on the disk, the information is still there. A format can easily be unformatted and information found.

U need to Erase ( http://en.wikipedia....ki/Data_erasure ), Depending on the information stored, although a single pass might be ok, doing a few would be better ( Can always be done over night ). In the old days this would be done in DOS / out of windows, might have changed now. This sets the whole partition or disk to random 0s and 1s.

[+BudMan]

"ignore the comments regarding doing just a format, this is nonsense."

http://support.microsoft.com/kb/941961
Change in the behavior of the format command in Windows Vista

The format command behavior has changed in Windows Vista. By default in Windows Vista, the format command writes zeros to the whole disk when a full format is performed. In Windows XP and in earlier versions of the Windows operating system, the format command does not write zeros to the whole disk when a full format is performed.

[Intrinsica]

MillionVoltss, on 01 July 2012 - 12:42, said:

Ignore the comments regarding doing just a format, this is nonsense.

A format deletes where the information is on the disk, the information is still there. A format can easily be unformatted and information found.

U need to Erase ( http://en.wikipedia....ki/Data_erasure ), Depending on the information stored, although a single pass might be ok, doing a few would be better ( Can always be done over night ). In the old days this would be done in DOS / out of windows, might have changed now. This sets the whole partition or disk to random 0s and 1s.

FUD.

If I write a series on 1's and 0's on a disk, then go through the whole disk again and replace everything with 1's, how will a program be able to tell where a 1 was a 0 before, and where a 1 should remain a 1? It can't.

A basic format does what you pointed out, it removes the headers. But once you do one pass on a disk you're fine.

[mikiem]

If you're really paranoid, or stored Top Secret government data on a hard drive, the drive needs to be physically destroyed. For everyone else there are all sorts of drive scrubbing apps available, McAfee for example includes this in at least some versions of their AV software.

Erasing or securely deleting files means overwriting that part of the hard drive's storage with new data, usually garbage but all ones or zeros, as with a full format works too. This is because data's stored all over the place on the hard drive's platter(s), with a Table of Contents at the front of the drive/partition recording where all the bits & pieces of each file are -- simply deleteing a file only removes its TOC entries. That's why all those utilities to recover lost files work -- you can fit all the pieces of a file back together like some sort of jigsaw puzzle [assuming all those pieces are still there, haven't yet been overwritten, which is why if there's something *Real* important you need to recover you click off the main power switch or pull the plug, running your recovery app(s) from a boot disc/USB stick]. Now, conventional hard drives work by having heads float above the disk platter(s) to read/write data -- since they float there's a very slight amount of wobble. If as a file is written one head happens to wobble to the right, then when it's overwritten that same head happens to wobble left, there could be traces of the original file remaining alongside the newly written data -- that's why erasing/scrubbing a drive usually means overwriting everything multiple times... the more passes you make the more chances the head(s) were on the right, the left, & everywhere in between overwriting data.

You can also erase, scrub, securely delete individual files, &/or all the free space to get rid of stuff without wiping the entire drive. In that case you might want to use an erasing app that goes after the unused portion of cluster blocks... On a conventional hard drive the storage space is divided up into small chunks & data's stored in those -- one way to think of it is if you set out a row of glasses & start pouring a bottle of your favorite beverage -- the last glass is likely to be only partially filled. If one of these blocks or chunks was completely filled, then only partly overwritten, there's old data still there that could potentially be recovered.

[mikiem]

Quote

Nobody will be able to read any kind of residual data from your drive after doing a full format twice. And your data wouldn't be worth that kind of trouble and cost anyway

Quote

As long as you write something over the sectors - then data can not be recovered. Doing multiple wipes is overkill, once is enough.

Purely FWIW I agree, but I still will either destroy an old drive I'm getting rid of, or use multiple passes if the drive's going to someone else... Connecting the drive to a PC/laptop I'm not using at the time & running whatever to erase that drive costs me only a few minutes connecting/disconnecting the drive & fireing up whatever app -- the [admitedly small amount of] additional peace of mind I get is well worth it to me. 'Sides, makes it harder for someone to get away with claiming they recovered this or that from the drive, they can't as easily get away with saying whatever files were on there when they got it & so on.

[Cosmin]

i've done in the morning the (only) format for the 3 partitions by using my windows 7 ultimate dvd.. I hope I'm ok with this, I'm not paranoid and the buyer is not an experienced user.. as I know. Hdd is on it's way to the client but my best friend that routes it still can help me.. should I?

[thunderrooster]

Get Parted Magic and do a secure erase. HDDerase will also do a secure erase. Secure erase is suppose to the best method. I have been told zero wiping is good enough. I would do more than that though. If your drive does not support secure erase Parted Magic has other methods. https://www.youtube....?v=g8t2ZXOMGKY. As mentioned before DBAN too.

[tomasarson]

BudMan, on 01 July 2012 - 12:04, said:

A full format in XP does nothing but remove the pointers and make sure the sectors can be read. This will not remove the ability to recover a file. If you are using vista or higher then it does write zero's and that would be good enough

As long as you write something over the sectors - then data can not be recovered. Doing multiple wipes is overkill, once is enough.

+1

a full format on xp doesnt write 0's and 1's. it just does a standard format then fully checks the disk.

i'm a fan of the shred command in linux myself. i just put my hdd in a usb enclosure. boot up my favorite linux live cd and shred -n 2 -fvz /dev/X

i think there's a ton of free erasing programs that you can make a live cd with. but it's been a while since i've looked up any.