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Learn How to Securely Delete Files in Windows

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When you delete a file in Windows, only the reference to the file is removed from the file system table. The file still exists on disk until other data overwrites it, leaving it vulnerable to recovery.

There are many tools available out there that allow you to securely delete files so they cannot be recovered. This article provides a summary of some of the free tools available out there, many of which are portable, allowing you to securely delete files you may temporarily save to public computers.

Eraser

Eraser makes it very easy to securely delete files, folders, or both. It overwrites the files being deleted with random data. There are several options for the number of times the files being deleted are overwritten with random data, including two versions of the US DoD 5220.22-M standard (3-pass and 7-pass) and the Gutmann method, which overwrites the file with random data 35 times.

You can immediately delete files and folders using the On-Demand interface or schedule files and folders to be securely deleted at a specific time using the Scheduler.

Eraser comes in a version you can install, which also allows you to add an option to the Windows Explorer context menu to securely erase files within Explorer. You can also download a portable version of Eraser you can take with you on a USB flash drive to delete files you save on other computers.

Download the installable version of Eraser from eraser.heidi.ie or the portable version from PortableApps.com.

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Freeraser

Freeraser is a free, portable tool that allows you to securely delete files using drag-and-drop. You can select to delete your files using a Fast method of filling the space with random data with one pass, using a Forced method that utilizes the DoD 5220.22M, 3-pass standard, or using the Ultimate, or Gutmann, method, deleting files by overwriting them with random data 35 times. Right-clicking on the Freeraser trash can displays a menu allowing you to manually select a file for deletion and to change the options for the program.

Download Freeraser from pendriveapps.com.

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Blank And Secure

Blank And Secure is another portable drag-and-drop secure file deletion tool. Simply, drag-and-drop files or folders to be deleted onto the middle box on the Blank And Secure window. You can specify how many times the files are to be overwritten by zeros by clicking the Overwrite X times button and selecting an option. The deletion operation can be delayed up to 9 seconds using the Delete Delay X sec. button.

Download Blank And Secure from pendriveapps.com.

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DP Shredder

DP Shredder is a portable, small program that allows you to securely delete files or directories and to overwrite the free space on a hard drive so files that were deleted previously without using secure methods cannot be recovered. You can easily select the method for deletion, which includes two US DoD-approved methods and the Gutmann method, and how many times (Rounds) the method will be applied.

Download DP Shredder from portablefreeware.com.

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SDelete

SDelete is a command line tool allowing you to overwrite the free space on your hard disk so any previously deleted data becomes unrecoverable. It is portable and can be run from a USB flash drive in a command prompt window. To get help with how to use the command, type “sdelete” (without the quotes) at the command prompt and press Enter.

Download SDelete from technet.microsoft.com.

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CCleaner

CCleaner is a program that removes unused, temporary files from your system, cleans up your internet history and cookies, contains a tool for cleaning the registry, and even allows you to clean up files from applications installed on your computer. The latest version offers a tool for wiping the free space on your hard drive. You can wipe the free space on a hard drive or the entire drive, securely deleting all data on the drive. There are four options for specifying how many times the data will be overwritten.

Download the installable version or the portable version of CCleaner from piriform.com.

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A program for secure deletion of files is a useful addition to your software toolbox, especially if you use different computers, some of which may be public machines.

Lori Kaufman is a freelance technical writer who likes to write geeky how-to articles to help make people's lives easier through the use of technology. She loves watching and reading mysteries and is an avid Doctor Who fan.

  • Published 09/1/11

Comments (27)

  1. bob

    thanks bro!

  2. D1G1TALD3ATH

    Eraser is teh s***! been using it forever.

  3. goek

    If I let a program erase/wipe files 35 times, does it wear off the HD?

  4. Jim Haynes

    I have found one of the better free ones to be Evidence Eliminator. Its Options selections allow one to do practically anything insofar as eliminating/deleting files, trash can, free space, or the entire drive.

  5. Paul DeLeeuw

    A word of warning: I used Ccleaner “wipe free space” on my Windows 7 32 bit 320 gB C: drive. Computer would not boot. System restore and Rollback did not fix. Chkdsk /f and sfc did not help. Windows boot disk options did not help. Forced reinstall. Beware.

  6. Marley

    Thanks Paul! I almost used ccleaner for that purpose … you just might have saved my life!

  7. rod

    RE Ccleaner: I have been using this program for a few months and have never experienced any problems with Windows start up after using it.
    The one problem I have found is that after using the registry tool it doesn’t erase some items it finds that it says it deletes when I click on “Fix All Issues”.

  8. snert

    I use File Shredder. It has 5 files levels of wiping. .

    1 simple pass, good enough for me.
    2 simple passes a little better.
    Dod 5220-22.m, decent enough for G’ment.
    Secure/7 passes.
    And Gutman w/ 35 passes.
    My take, the ’35 passes’ would add some wear on the HD. It would have to.
    If it was used, say, every weekend, the wear could be significant.

    Paul; I’ve used CCleaner’s Wipe Free Space some several times and never
    had a problem. Different Systems, Different Strokes.

  9. Ushindi

    While I use Freeraser and CCleaner at various times, my favorite shredder is Moo0 File Shredder, which I read about here on How-to Geek. It was in an article by Asian Angel, back in August, 2009, so I’ve been using it for two years now, and swear by it. I also tried out Moo0 Disc Cleaner and still use that on a regular basis. Both are freeware, BTW.
    I also have never had a problem with CCleaner when wiping free space – in fact, I just ran it overnight on this computer I’m currently using, and have used it in the past for that purpose many times.

  10. keltari

    Dont think for a second that a “DoD” level wipe will prevent the DoD or other agencies from recovering the file. The DoD still destroys their hard drives to prevent data theft.

  11. musicwalt

    I have heard that (when using the console) I can “copy as” (old filename) and the new (replacement file) will completely overwrite any existing data in the original file. True?

  12. Josh

    With CCleaner, a 3-write pass is enough to stop most people. Corporations use 3 before they sell their old machines. If someone really wants your info, go for the 35-write pass. Expensive machines can get your data even after 60 wipes, but 35 will stop anyone that doesn’t work for a data recovery company. And if you really need secure deletion, destroy your hard drive.

    As for permanently deleting stuff off of SSD’s, you can’t. They have backup sections that most programs (including the OS itself) are not able to discover. The point is to keep the SSD alive if a section fails, so no, they aren’t trying to steal your data.

    goek, wiping your hard drive with a set of random 1′s and 0′s will only wear it down as much as if you actually put real files on it.

    rod, that’s because you deleted registry entries that had others depending on them, so they didn’t show up as unusable until after the first registry clean.

  13. Josh

    ahh, I need to refresh my pages more often…

    musicwalt, recovery is eash when someone just deleted something, but it is much harder to recover something that has been replaced by other data.
    Basically instead of random 1′s and 0′s writing over your old file, your wrote over the old file with non-random 1′s and 0′s (those being the new file).

  14. DieSse

    “My take, the ’35 passes’ would add some wear on the HD. It would have to.
    If it was used, say, every weekend, the wear could be significant.”

    Rubbish – writing to a drive doesn’t “add wear”. That’s what drives do all the time, some files, like the pagefile may be rewritten hundreds or even thousands of times a day.

  15. DieSse

    The only reason that security agencies physically destroy drives is that people and procedures can’t be trusted to erase data securely. A simple “shred-it” (yes hard drives can be shredded) is just simpler, faster and cheaper.

    It is very, very difficult to recover data that has been overwritten once – let alone 35 times with random patterns. Much more likely that the data exists somewhere else on the drive in shadow copies and the like.

  16. Wayne

    When you’re done with them, just dip them in Liquid Nitrogen and smash them with a hammer.

    <>

  17. StevenTorrey

    I use CCcleaner practically every evening. Never had a problem with it. Though every time I use it, if I want to access my mail, I have to sign in again. More annoying than anything but if there was a way not to have the mail discontiued, I would appreciate knowing.

  18. Val

    LOL @ Wayne :)

  19. Josh

    Steven, you are cleaning out your login information with CCleaner. Find out which program you use for mail and unclick that part that says delete passwords/login info.

  20. Ray

    Steven, In CCleaner go to OPTIONS, COOKIES, and move your email/game site cookies to the right side to save them so it maintains your log in cookie.

  21. williamB

    You should be aware that using the 35x Gutmann method of wiping has been declared obsolete by Peter Gutmann himself a long time ago. He wrote a long essay about secure deletion in general and on his own method on the site of Auckland University. Especially interesting are the epilogues in it. There he states that his own method was written a long time ago to be used on hard drives that no-one of us are probably using anymore. Techniques have changed a lot.

    Quote: “As the paper says, “A good scrubbing with random data will do about as well as can be expected”. This was true in 1996, and is still true now.”.

    Further down the same article he writes that Gutmann recommends: “There are two ways that you can delete data from magnetic media, using software or by physically destroying the media. For the software-only option, to delete individual files under Windows I use Eraser and under Linux I use shred, which is included in the GNU coreutils and is therefore in pretty much every Linux distro. To erase entire drives I use DBAN, which allows you to create a bootable CD/DVD running a stripped-down Linux kernel from which you can erase pretty much any media. All of these applications are free and open-source/GPLed, there’s no need to pay for commercial equivalents when you’ve got these available, and they’re as good as or better than many commercial apps that I’ve seen. To erase SSDs…. well, you’re on your own there.”

    Source: h t t p://www.cs.auckland.ac.nz/~pgut001/pubs/secure_del.html

    Apologies for my lengthy contribution but it seemed functional.

  22. Ushindi

    Jeez, keltari – if the DoD is after you, you’ve got a lot more to worry about than whether to use CCleaner or Moo File Shredder…lol

  23. The Geek

    WilliamB is completely correct – multiple-pass delete is unnecessary.

  24. Luis B

    What are the chances of recovering anything after a single full drive pass on an off-the-shelf magnetic HDD? Any real world evidence? Just wondering.

  25. Nawlins Jeaux

    I’ve used BC Wipe since early 2002, updating as req’d. Std. DoD 7 pass wipe. The only issue I ever had was with Vista. BC Wipe turns off system restore (points), requiring the user to create one after wiping. What I like most about BC Wipe is that you can add it to the right click menu for the Recycle Bin, and wipe directly.

  26. Zarky

    I have been using CCleaner for as long as it exist, no problem whatsoever. iF you want to delete data safely there is only one way, use a hammer! LOL!!!

  27. Abet

    I have known a lot of apps that can help us securely delete files but I haven’t heard of anything yet capable of restoring deleted files in a hard disk using NTFS file system unless you only moved your file to the recycle bin. My problem is not on the secure deletion of files but in restoring accidentally deleted files, that is, not moved to the recycle bin, as in, deleted for good but not intentionally. Does that sound confusing? Here’s an example. I was working on a laptop with a touch pad on to deleting unwanted files. I selected my files, press shift+del and hit ok without noticing that my palm accidentally touched and tapped on the touch pad that changed my selection to another file which was very important to me. And just before I was able to cancel it, my file was already deleted.

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