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georgecooldude

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Delete data for good so it cannot be retrieved from the hard drive.

I need to delete some data off a few of my old hard drives for good. So they cannot ever be recovered.
I want to keep the hard drive in a working order of some sort so I could either sell it or give it away to a friend or something.

Links to apps, How they work, why they are good.

The more info the better
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SheharyaarSaahil
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Blowtorch. :-)
Whoops. Ya wanna keep it in working order. Oh, well.
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Cyber-Dude

SheharyaarSaahil, as usual - good advice there...

Cyber
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SheharyaarSaahil solution looks good :-)

But DVation191 mentioned this would not be secure and could easily be recovered.

Could I have some more infomation on both packages

And PsiCopy the  Blowtorch is a good idea! Except I don't think anyone would want to buy a melted hard drive ;-)
And generally how long would it take to wipe clean a 40gig drive, a 80 gig drive and a 160 gig drive?

Not that I want to wipe them all. I'm just interested how long it would take for each size. The 80 and 160 gig are 7200rpm with 8 mb buffer. The 40gb has a 5200rpm with a 2mb buffer. All drives are western digitial
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"KillDisk is a low level format utility. This mens that all the magnetic surface of the drive is reset to '0's thus eliminating the chance of recovering data in any way."
This is not true to physics. The writing of a zero changes the polarity, but still leaves residual magnatism that professional data recovery labs can recover from. Obviously this is the case because a "zero'ing" out of the drive is the LEAST secure algorithm for erasing data from a hard drive....if this wasn't the case, nobody would have bothered coming up with Department of Defence and Gutmann algorithms to overwrite the data in such a way that using residual polarity to extract data becomes physically impossible. The more advanced the algorithm used, the longer it will take.

I could get into the physics of it, but I won't bother when so much has already been written about it. If you feel the need...
Secure Deletion of Data from Magnetic and Solid-State Memory
http://www.cs.auckland.ac.nz/~pgut001/pubs/secure_del.html
a very small except from the above article...

"To erase magnetic media, we need to overwrite it many times with alternating patterns in order to expose it to a magnetic field oscillating fast enough that it does the desired flipping of the magnetic domains in a reasonable amount of time."

"Zero'ing" out a drive, as what Killdisk does, overwrites the magnetic media ONCE, not many times.
"Zero'ing" out a drive, as what Killdisk does, overwrites the magnetic media with ONE pattern, a zero, not alternting patterns.

This is why more advanced algorithms like Gutmann's was created...because it provides many overwrites with many alternating patterns...which is why it is such an effective algorithm for erasing data permanently.

georgecooldude..... if u are a home user and just want not to give a hard drive to another friend so that he\she can recover ur files easily. then u can try KillDisk..... and after that for making sure, use urself a data recovery software to check if u can read any data which was present on ur hard drive.... if u cannot read then ur fried will also be unable to read it :)

its good for home and normal users, coz we use normal data recovery softwares for undeleting data, and the normal data recovery softwares dont use the strategy which is used to "recover" the data at defence level.... they need high security coz they have big doubts..... the enemies can use advanced tools to recover that data !!

But for normal users,,,,, we use normal zero writing tools and normal recovering tools,,, and KillDisk can do it, i have used it for once, and when i tested with GetDataBack, he was unable to read anything from the drive.... so keep it simple and normal and try it urself :)
DVation191; the link you sent does not contredict what I just stated. There are few methods to LLF and according to the KillDisk manufacturer, its software commits LLF by using the 'One Pass Zeros' method. Etherway; as I stated, if the author does not trust any 3rd party software to do LLF, it can always use the manufacturer's utilities (if available) to do so;

Links:
KillDisk features:
http://www.killdisk.com/features.htm

A little bit more about the method:
http://www.active-eraser.com/notes.htm

Hope that sorts things out...
:)

Cyber
I appologize if my point wasn't clear. All I was trying to say is that writing 0's to a drive does not eliminate *all* possibility of recovery. That method will work for some software-based recovery tools, but it's no match for a data recovery lab.
Is there any match for a data recovery lab?

If not I'll stick with normal data deletion.


Also if i rename a file, 2004report.doc to systemfile.sys to try and hide a file and do a deletion using the 0's method does the original name still reside on the hard drive? Does renaming files help in any way?
Well that's what I was attempting to say here...
The physic's of magnetism allow for data retrieval even after being overwritten with a zero. If you overwrite the file many times with varying patterns, it's nearly impossible. (The Department of Defense uses an algorithm like that...and hey, if it's good enough for them, it should be good enough for you!).

So to answer your question, yes, there is a match. The match would be the data erasing algorithm that overwrites many times with varying patterns (an algorithm, not a series of 0's).

Found the following at:

http://www.stellarinfo.com/data-eraser.htm

Wiping standards followed for complete data destruction

Stellar Wipe- File Eraser Utility conforms to the following International Wiping standards to ensure complete data destruction.


DoD.5200.22-M (3)
DoD.5200.28-STD (7)
B. Schneier's algorithm (7 passes)
DoD.5200.22-M (3)

The unused space or file or disk is wiped using Department of Defense (US) standard 5220.22-M (3). Provides high-grade data wiping filling the unused space or file with a special digital pattern through 3 passes.

DoD.5200.28-STD (7)

The unused space or file or disk is wiped using Department of Defense (US) standard 5200.28-STD (7). Provides high-grade data wiping filling the unused space or file with a special digital pattern through 7 passes.

B.Schneier's algorithm(7 passes)

The unused space or file or disk is wiped using B.Schneier's algorithm. Provides high-grade data wiping filling the unused space or file with a special digital pattern through 7 passes.

In addition 3 basic wiping methods are also available.
Thanks guys.

I split points. Hope i didnt miss anyone. :-)