cryingvalor

-hey guys do you know a good, free easy to use tool in formatting HDD. completely removing all files making it unrecoverable.

8210GUY

There isn't one as far as I know, not if someone wanted it bad enough that is like the FBI for example, BUT, you can make it as impossible as it can be for average people to not be able to recover anything, there may be other tools around, but Spybot has what it calls a secure shredder under it's advanced tools and that is free if that helps.

Doby

http://dban.sourceforge.net/

That could work for you but it is said that the only true way to distroy data is with a sledge hammer

koala

NecroFile will delete all your files (or just selected files/folders) and write over the space repeatedly so they cannot be recovered.
Another good one is Sure Delete

Done_Fishin

With the exception of destroying the drive the only way to stop anyonefrom gaining access to your data is to put the drive in a drawer and not give it to anyone!

To destroy the data on the drive to make it really difficult to recover will take several days leaving a piece of software runing that will write over and over and over to the disk surface burying the old data with new useless data. If you've got a PC and a week to spare, give it a try. Then try for a couple of weeks to see if any data can be recovered or not.

koala

I agree. It can take a long time to make data completely unrecoverable. I'm in the process of giving one of my old hard drives to a friend. I used NecroFile to overwrite the data and empty space several times and it took 2 days to wipe 80gb to a standard where no recovery software can detect any data.

8210GUY

Like I said there is no real way to do it fully, one exception maybe being dissolve the drive in an acid bath, but even drives destroyed by fire etc so they are totally useless and supposedly gone forever can still have some data recoverable by the top people like FBI etc, so sledge hammers and fires still aren't enough in their own right to guarantee a result.

dmitryk

A moment of truth.... :-)

This is complete myth blown out of proportion. I work for a data recovery company and drive manufacture. Believe nobody, FBI, CIA, etc has ability to recover data from simple one pass erase. DoD Standard of 3 pass is a fake. You can do 10 - 100 or 1 pass it will not make it worse or better from point of erasing data on the drive.

What everybody worries about that Read Head and Write head inside of the drive are geometrically different.... where write head when erase data of the track will leave bands of previous data. It is supposedly possible to fly over the bands and read data.... Bull*t!!!

It's like many things in this world - Scare Has Big Eyes.....

koala

Hi Dmitry. Can you explain more about the efficiency of multipass erasing. It's good to get the chance to hear from an expert on the subject.

I've used various delete programs using 1 pass and have been able to recover the data using GetDataBack and PC Inspector. 3-7 passes makes it unrecoverable (as far as I can tell). So what's the best and quickest way to achieve satisfactory results? Thanks

dmitryk

As you figure out one program is different from another.

You can't recover anything from one pass erase. So the program you been using didn't done one pass erase. Btw, it is take significant amount of time to do one pass erase.(e.g. 750GB drive will take about 4-5hr at least.) So anything which took less then 20-30 min on 40GB is not erasing data.

DoD erase was created based on somebody proposal who had uneducated knowledge of how HDD function. Many variation of multipass erase will refer to flipping bits, writing different patterns etc, to make sure that data is has bits has been flipped to a different direction.....
Well the technology behind writing a single bit (actually a pattern of bits) is design to address ever growing density of the drive. Magnetic domains are located so close to each other, that they interact and detection (recovery) of the bits takes significant mathematical computation. Data on the drive is scrambled with various polynomials and will never going to be same as what you were intended to write there. Read/Write channel using Partial Response Maximum Likelihood (PRML) technology decode and encode sequence of bits with special pattern from/to drive. Every manufacture use it's own polynomial and ways to encode data on the disk. That as well differ between different models as well.
When we attempting to influence what is written on the drive with different patterns we won't be able to achieve that because of the variation of how data is scrambled on disk.
When we try to write multiple passes we trying to influence bit flipping and band erasure. It is no way to predict where the head will fly next time relative to the band. In a sense you can't predict exactly if head will go through the same path or not. E.g. you know that head will follow Highway 30 but you can't tell which lane it will take.
It is not possible to use drive electronics to read bands since it has been design for normal strength signal. The only to way to get to it is use Magnetic Force Microscopy. To image one disk under MFM it will take months to few years. After image is obtained data has to be descrambled, and not normal data but band data which already lost its signal strength. Bunch other additional processes has to be followed to reconstruct where particular sectors were located in the filesystem. I didn’t mention another problem …. How you will identify when that data was erased… was just yesterday when you run erase program or 2 years ago when you delete that file….

Check links to white papers we published...
1. http://forums.actionfront.com/showthread.php?t=19
2. http://www.actionfront.com/whitepape...20Preprint.pdf

and Wikipedia article on PRML http://en.wikipedia.org/wiki/PRML

koala

Thanks for the detailed reply. Very informative.