How to overwrite the free hard drive space?

GuessWhat

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Hi, is there any tool or something that could help me? I really have to get rid of some files in my Windows 7 x64.


thank you,
Nik
 
Solution
Ricky_Critic is right. I agree with this: "..these programs have ensured that the files are completely erased physically from the hard drive..."

If the program is good, really good (as Mil Shield or CCleaner) then the hackers cannot find any information about you. The whole information will be overwritten, so no matter who hacker will break your computer.

jcksn

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If you had a file with sensitive content and you have deleted it without shredding, its content will remain on the disk for a very long time.This is happening because when Windows deletes a file, it does not actually clean the file contents. Instead, it just declares the space that was taken by the file as empty. This makes file deletion very fast but is a real problem when the deleted file had a private content.

But enough talking! ;)

I use this tool. It overwrites very quickly the whole free space of a particular disk:
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ricky_critic

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The whole process of erasing files from the hard drive is very tedious and hard. Some people believe that one overwrite will not do. They say that it will take more, possibly even more than twenty overwrites. Some even believe that the most determined and talented hackers can still recover the file, even though it has gone to more than 20 rewrites. To be absolutely sure that the files are no longer recoverable, many people create software that intentionally write blank characters over them. These applications do the overwrite several times in a few seconds. By doing so, these programs have ensured that the files are completely erased physically from the hard drive. Even if the hackers can still retrieve some bits of information, it is no longer that comprehensible to be reconstructed.
 

huron

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What Ricky said is why these secure erase programs exist. They write a pattern of 0s and 1s multiple times to overwrite the entire sector, so it leaves no slack space for file recovery.

From what I have read, there is a contest done yearly where only 0s are written in one pass, and the best forensics people in the world have yet to recover anything (wish I could find the article again). Typical wiping programs will allow DoD wiping, which can be done in 7 passes - pretty well assured that it will be overwritten and not recoverable.
 

820911AL

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Ricky_Critic is right. I agree with this: "..these programs have ensured that the files are completely erased physically from the hard drive..."

If the program is good, really good (as Mil Shield or CCleaner) then the hackers cannot find any information about you. The whole information will be overwritten, so no matter who hacker will break your computer.
 
Solution

number13

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Formatting only marks the files that can be over written, or declares the space available, the only Programs that I know of the do real "wiping"(writing zero's to the drive), do it to the entire drive not just a small space, these can be found on The Ultimate Boot CD(UBCD) and Mil Sheild and either Acronis or Hirens, but UBCD is free, my understanding is that 7 passes of "0" overwriting are necessary to insure DoD compliance with sensitive data destruction, but 1 pass for applications and windows cannot see anything
 

jedimasterben

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The DoD does not wipe with just 0, though. They do 7 passes total, but one is just 0s, one is 1, one is 0101010101, one is random characters, etc. And, if anyone is interested, as of 2007, just overwriting is no longer allowed to meet DoD standards, it has to be either degaussed or physically destroyed. :)
 

Kewlx25

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Typically, to recover data from a HD after a triple pass of random data, you need to remove the platters and use specialized hardware to read the platters. Then you need a specialist who is skilled in massaging the data since there's going to be a TON of random noise. This can take a long long while and the hardware alone would require government style budgets.
 

ricky_critic

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CCleaner has a "free space" cleaner, plus much, much more. You can clean as you delete your files, overwriting them up to 35 times, if you want to take it that far. But keep one thing in mind, with the "free space" overwriters, if you clean 100% of you free space, you may overwrite all of your restore points. You certainly don't want that to happen.

You have another option, which actually recovers your deleted files, so that you may choose to recover or delete the found files. A two in one deal. The program name is Recuva, written by the same group as CCleaner. What you do is a "deep scan", which may take a while. Afterwards, you have the option of recovery or deletion of the files. They also can be overwritten up to 35 times, but on a large drive, this will take some time. You can actually use your computer while the files are being overwritten.
 

Fotal1ty

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There is such thing as full PC safety and it includes strong passwords, privacy protection tools, firewalls, anti-spam tools, anti-viruses tools...., and of course free PC space wiping (shredding) tools.

I recommend Mil shield here:
http://www.milincorporated.com/milshield2.html

It overwrites deeply with in very secure ways, files, structures and free hard disk space.