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When you hit the delete button, where does that file go? Does it just evaporate and leave a blank space on your drive? If you’ve been around computers long enough, you know that’s not what happens. But if you’re mostly an email and Facebook type of computer user, you might not know, or not even thought about it.

You should think about it though, for a couple reasons. The first reason is so that you know you might be able to recover an accidentally deleted file Turn Back Time: 4 Tools & Tips To Restore Deleted Files In Windows Turn Back Time: 4 Tools & Tips To Restore Deleted Files In Windows One of Windows' biggest flaws could be your rescue, should you ever accidentally delete an important file: The Windows file system does not actually delete files. Until they are overwritten, deleted files can be restored. Read More . The second reason is so you know that, if you can recover a file you deleted, so can someone else.

What Happens to a File When It Is Deleted

Hard Disk Drives (HDDs)

When you delete a file it goes to the Recycle Bin. That gives you a chance to recover it in case you accidentally deleted it and need it back. But what happens when you delete it from the Recycle Bin? Actually, not much at all. The file doesn’t move or go anywhere. In fact, when you moved it to the Recycle Bin, it didn’t physically move there either. All that happened was an index got updated to say that the file is in the Recycle Bin, not the Documents folder.

The index is called the Master File Table (MFT) for Hard Disk Drives. It looks like this. The left-most column are the block addresses. The middle column shows data in hex code. the right column shows what that data would like as plain text.

master-file-table-example

When the file is ‘deleted’ the information stays on the drive, but the MFT is changed to say, “Hey, you know that spot where Secret-File.txt was? Yeah, Computer, you can now put data there if you want. We don’t need it anymore.” Until the computer puts data in that spot, the Secret-File.txt data remains. It could be minutes, days, weeks, or months until that data is overwritten Why It Is Impossible To Recover Data From An Overwritten Hard Drive [Technology Explained] Why It Is Impossible To Recover Data From An Overwritten Hard Drive [Technology Explained] Recovering deleted data from a hard drive is generally possible because typically the actual data is not deleted. Instead, information about where the data is stored is removed. In this article I will explain how... Read More . Kind of like a condemned house sitting on a lot. It’s not usable, but it’s still there until the bulldozer comes and they build something else.

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Here’s an example. The left column shows red Xs for MFT locations that have been set to be overwritten, the one with the page icon is marked to stay. The right column shows the data that is still in that location, even though you can’t find it with Windows Explorer. See the problem with ordinary deletes now?

MFT-NTFSWalker

Solid State Drives (SSDs)

It’s not exactly the same for Solid State Drives. SSDs are always shifting files around, randomly. So, figuratively speaking, if you deleted a file from location 2871, the deleted info may, sooner or later, get moved off to another random location, until at some point in time the SSD decides to finally overwrite that file. How do you target the old file for secure deletion on an SSD, then?

Well, you can’t really. A group of engineers at the University of California studied how difficult it is to erase data from an SSD. Trying to securely erase a single file left behind anywhere from 4 to 75% of the information. And it’s tough on the drive. What you can do is make sure you encrypt your SSD Free Military-Grade Privacy For Your Files: How Bitlocker Works [Windows] Free Military-Grade Privacy For Your Files: How Bitlocker Works [Windows] Ever heard that quote about trying to explain how a television works to an ant? I'm not calling you an ant, even though you are hard-working and enjoy the occasional sip of aphid milk. What... Read More , and make sure that you’ve got an SSD drive with TRIM capability Why TRIM is Important to Solid State Hard Drives? [Technology Explained] Why TRIM is Important to Solid State Hard Drives? [Technology Explained] Read More .

got-trim-ssd

This isn’t a problem for most people, but you might be concerned that people could still access that deleted information. Maybe you handle sensitive medical documents, or you’re an international art thief, or just a little paranoid like me. How do you securely get rid of that data, immediately and forever?

What Is ‘Secure’?

Before we get into the nuts and bolts of secure data deletion, we need to look at what secure means. Secure means whatever you think it means. If you’re happy with the level of security you have, then it’s secure. If the data you don’t want recovered isn’t life threatening, then the measures you take to delete it don’t need to be as severe as deleting the security codes for the last sample of smallpox off the CDC’s servers.

Let’s take a look at the methods in order of  least secure to most secure. Until we get to entire drive deletion, these methods will only apply to traditional HDDs.

Least Secure Method

Simply delete the file in your Windows Explorer and empty the Recycle Bin. Unless you think someone is going to come along with data recovery software and look for that file in the next week or so, that will probably be secure enough. Examples of information like this could be anything from a silly animated GIF to a letter to your Nan. You really should write to her. She misses you, you know.

salt-lake-grandma

Mildly Secure Method (HDD Only)

As we talked about, overwriting data is a pretty good way to obscure the old data. You can do this on a file by file basis with programs that are commonly referred to as file shredders Free File Shredder: Permanently Remove Files & Folders From Your System Free File Shredder: Permanently Remove Files & Folders From Your System Read More . Although the interfaces for these utilities can differ, the method of operation is essentially the same – delete the old file, then write zeroes to the places on the HDD where the file used to be. These tools are only mildly secure, because you have to make sure you use them when you need them. If you want to securely delete a file with your Social Security Number on it, but forget to use the shredder, that info will still be sitting on your drive for awhile.

file-shredder

Examples of use for this method is where the person occasionally deals with sensitive information that pertains only to them. It might be the odd copy of a tax return, or a bank statement that you want to delete. That’s where file shredders are most handy.

Moderately Secure Method (HDD Only)

A more moderately secure method to delete information from your drives is to use software that allows you to wipe free space on your drives. CCleaner is a favourite Optimize Your System To Run At Its Best With CCleaner Optimize Your System To Run At Its Best With CCleaner Over the last two years, CCleaner has changed quite a bit in terms of version numbers...up now to version 3.10 at the time of this writing. While visually the program actually hasn't changed much (it's... Read More for this task. When you choose the Wipe Free Space option, it writes zeroes to the blocks where files used to be. The difference between this and the shredders is that wiping free space takes care of ALL deleted files. It’s just that little bit more thorough. The catch is that this method takes a fair bit of time and should be scheduled or you’ll forget to do it frequently enough.

CCleaner-wipe-free-space

Examples of good uses for this are for people who frequently delete files that are quite sensitive. Maybe they are heavy online bankers or do some online trading. Perhaps they have just backed up their important info to an encrypted external drive and don’t need it on the computer anymore.

Most Secure Method (HDD & SSD)

The most secure methods are really for deleting the entire contents of a drive. Yet again, because of the differences between HDDs and SSDs, the same methods don’t apply to both. Chose the appropriate one for your drive and situation.

Examples where you’d want to go to this level include switching to a new computer which will have the info, but you’re keeping, selling, or disposing of the old computer. Perhaps you are re-purposing a computer from an information-sensitive use to a more day-to-day use.

HDD – Formatting

Formatting is a catch-all term for a few different things. It can mean simply deleting the MFT so it appears like all the data is gone, but it isn’t. It’s still there and intact until overwritten. Or, it can mean true formatting, known as low-level formatting 5 Tools To Permanently Delete Sensitive Data From Your Hard Drive [Windows] 5 Tools To Permanently Delete Sensitive Data From Your Hard Drive [Windows] In a recent article I explained why it is impossible to recover data from a hard drive after overwriting it. In that post I mentioned that simply deleting files or formatting your hard drive typically... Read More , which overwrites all the data with zeroes. You can’t low-level format your entire hard drive from within Windows. You’ll need a formatting utility that you can boot your computer into, like Darik’s Boot and Nuke.

dariks-boot-and-nuke

You might be tempted to choose one of the hardcore multipass methods, but that’s probably going to be overkill. Especially if you want it done quick and don’t want to shorten the life of your hard drive. The RCMP TSSIT OPS-II or DoD Short methods are sufficient. RCMP is the Royal Canadian Mounted Police and the DoD is the British Department of Defence. Good enough for them should be good enough for you.

SSD – Manufacturer’s Utility

Most SSD manufacturers have a utility for managing and securely erasing their SSDs. Tim Brookes was kind enough to compile a list of links for the top manufacturers in his article, How To Securely Erase Your SSD Without Destroying It How To Securely Erase Your SSD Without Destroying It How To Securely Erase Your SSD Without Destroying It SSDs can only be written to a limited number of times. This is a challenge, particularly for erasing data and doing so securely, which can vastly reduce performance and shorten SSD drive life. Read More .

erase-ssd-intel

Download: Intel Solid State Toolbox / OCZ Toolbox / Corsair SSD Toolbox / Samsung Magician / SanDisk SSD Toolkit

Paranoid Method (HDD and SSD)

The National Institute of Science and Technology has a policy to deal with the destruction of extremely sensitive data. It’s even more aggressive than what the RCMP or DoD use, so it will destroy your data to the point where not even Sherlock Holmes riding on Hercule Poirot’s back with Frank Columbo leading them around would get anything out of it.

Disintergrate. Shred. Pulverize. Incinerate.

melted-hard-disk-drive

That’s not hyperbole, that’s NIST’s actual standard. Oh, and to meet the grade you have to find a NIST licensed incinerator to do the job. That job in the picture above wouldn’t be good enough.

 What Will You Do?

You’ve got the knowledge and some resources now. It’s up to you what you will do with them. However, if you’re not already using several techniques to keep your information safe from prying eyes, secure deletion shouldn’t be your first concern. If someone already has your info, it doesn’t matter how you delete your copy.

What method do you use to delete files securely? Are you happy with it? Ever not been able to delete a file? Let’s talk about it.

Image Credits: Deleted File Hacked by Network Cables via Shutterstock, MFT in GHex Screenshot via SANS.org, Intel X25-M Solid-State Drive, Cutting head of a paper shredder, Burned Hard Disk via WikiMedia, DBAN Screenshot via DBAN, Salt Lake Grandma via Flickr.

  1. Bob M
    August 26, 2016 at 7:58 pm

    Not sure if the article mentioned this, but here's another strategy:

    If you have ccleaner or some other cleaner software that securely empties the recycle bin, just throw stuff in the recycle bin.

    Then, periodically, do a secure empty of the recycle bin, and never use the built in command to empty the recycle bin.

    If your browser sends cached files to the recycle bin (which I am supposing is true but I'm not absolutely sure on this point), then this strategy would also work to get rid of stuff you looked at in the browser.

    Following this strategy would eliminate having to wipe free space, unless someone has other info to add about programs that bypass the recycle bin and just delete files.

  2. george
    April 29, 2016 at 7:48 am

    (Sorry for my language deficiencies, English is not my first language)

    I know this is an old article, but i think we didn't talked enough about crypted storage.

    If you store your data in an encrypted partiton and you don't need it anymore, you just simply delete that partition and create a new one.
    If the storage is broken and you used good crypt software and secure password, than you don't need to do anithing.

    Of course you could ask, what if someone somehow decrypts the broken drive.
    There is a good solution for that.
    So when the secured partitions MFT and the crypted header files are stored in a differend drive (like a thumbdive), than anyone who would try to restore the drive could only see useless random data. They doesn't even know if it was a crypted partition or not.
    Not to mention the crypt algrithm or anithyng else.
    As long as I know it is impossible to restore a crypted partition without the header fies.

    About the formatting:
    You can reformat or delete only the working hdds or ssds.
    If it is broken you can't do anithing except buning it with fire ot something like that :)
    So the main question is why the hell would anyone drop out a completly good hdd or ssd?

    • Guy McDowell
      May 20, 2016 at 7:55 pm

      Usually, it's a matter of company policy not any real practical reason.

  3. DarkyD
    January 29, 2015 at 2:51 am

    Another simple way to delete everything would be to totally fill the drive with useless information like large games. This would overwrite your files them uninstall them.
    Simple

    • Guy
      January 29, 2015 at 2:06 pm

      Hi DarkyD,

      Sort of, but not exactly.

      Files that have been overwritten may still be recovered, especially by data recovery specialists. That's why the preferred method is to use a utility that will perform several passes of erasing the disk and, in some methods, writing garbage data to the disk.

      • Kevin Skipp
        October 26, 2015 at 10:07 am

        Really? name one....name one company that offers a data recovery service for a zero filled hard drive. They all - even the police - use software methods, they look at the data on the drive, into the freespace, and see if those 1s and 0s fit with any known file formats and what they are. If the freespace says 0000000000000000 ....or indeed FFFFFFFFFFFFFF, then there's clearly nothing they can do to turn that into a file. There is a theory that if you actually magnetically analyse the platter surface then you can see what's underneath. i.e. the magnetic charge for a 1 that's overwritten a 0 is different to a 1 that's on top of another 1. Then the theory goes really nuts and says that a 1 on top of a 0 on top of a 0 on top of a 1 can all be identified and differentiated between. However this variance would be different for every drive, they'd all have different tolerances and performance figures. Also the sheer size of the jigsaw puzzle you'd end up with would be outrageous. And at the end of the day it's just a nice theory - there is nobody who does it. The multipass method was due to different data encoding methods on old HDDs, it was NOT because multiple writes were needed, it was simply that some writes wouldn't work on some drives with unusual encoding methods. But Gutmann himself who invented the method, says that anybody using it today on a SATA drive on a windows computer is doing nothing more that reciting voodoo incantations. One write of 0s or 1s or random data will suffice.

        • Alex
          March 18, 2016 at 2:56 pm

          Kevin is this also correct for SSD?

        • Guy McDowell
          March 29, 2016 at 11:38 pm

          Hey Kevin,

          Thank you for your insight.

          But to be fair, DarkyD said, "Another simple way to delete everything would be to totally fill the drive with useless information like large games. This would overwrite your files them uninstall them."

          Here's my problem with that. You're probably never going to completely overwrite every single bit on that drive. Chances are there will be several sectors not overwritten, and data there could be recovered.

          As for a zero-overwrite, sure, why would anyone go through the trouble of trying to perform an off-track read to try to recover a little data. And by little, I mean maybe a few bits out of hundreds of gigs. But...it's theoretically possible, right?

          Probable? No. Practical? Hell no. But possible. And who knows what tomorrow's technology might bring?

  4. Phoenix
    July 7, 2014 at 1:39 pm

    Firstly, brilliant article Guy!!!

    This is my first time here and this is the best description of what happens to a file once it
    is deleted that I have ever read.

    However, how do the solutions suggested in the links below (although a little old) compare
    with your suggestions?

    They advocate using free software that provide military-grade wipe and file eradication to
    delete files or drives (including SSD) beyond recovery:

    http://www.ghacks.net/2010/06/20/delete-data-on-ssd-permanently/

    http://www.brighthub.com/computing/smb-security/reviews/44746.aspx

    Thanks again...

    I look forward to your response.

    Phoenix

  5. Derek
    June 8, 2014 at 3:22 pm

    The folks who shred my hard drives also shred my private and confidential papers, they have a big shredder in a truck that comes to the house. They are a local firm (St. Louis, MO), but I,m sure any shredding service with similar equipment can do the job.

  6. Derek
    June 6, 2014 at 3:11 am

    I use a service that shreds the hard drive into tiny pieces; costs $10 per drive. Seems to be effective. Derek.

    • Guy M
      June 8, 2014 at 12:57 am

      Really? That's pretty cool! How about you give them a plug here?

  7. Cloksin
    June 6, 2014 at 12:14 am

    I work for a quasi-government agency and as government we're not allowed to throw anything away. If we're getting rid of something we have to make it available for surplus sale. (govdeals.com if you're looking for stuff the government is getting rid of).

    We're also in the process of swapping out all our HDDs for SSDs. When we get rid of them we use a program called KillDisk from Active@. It has pretty much every HDD wipe and Kill standard available. The one we use is the 3 pass DoD one. On pass one it writes 0 to every byte, pass two it writes F to every byte, the third pass is random.

    Depending on the size of the drive though I've seen this take close to a full day.

    • Guy M
      June 8, 2014 at 1:07 am

      Great info! Thank you for sharing. That's the practice for a lot of different gov'ts to have to auction or surplus sale items, since they were paid for with public funds. Good call on a way to get some cheap equipment.
      Also thank you for the first hand info on doing wipes. It does take a LONG time. That's when you realize just how much storage is really on a drive.

  8. SH
    June 5, 2014 at 4:33 am

    Very interesting article - thanks for posting it. A couple or three questions though about by OEM SSD (Lenovo X1): (1) is running ccleaner at startup (using 3 pass overwrite) to clean out my recycle bin a waste of time; (2) is there some way of telling if my OED SSD has TRIM; and (3) do cloud back up systems (Mozy in my case) play nicely with encrypted drives? Again, thanks for the useful article

    • Guy M
      June 5, 2014 at 12:05 pm

      Thank you!
      1) Yes.
      2) You could research the specs of your computer to find out the details about your drive and look up if it has TRIM or not on the web. There are also software utilities that can help you check for TRIM and if it's working or not. Trimcheck and Crystal DiskInfo are two. And you can use the cmd prompt with the command fsutil behavior query disabledeletenotify to make sure TRIM is enabled in Windows. DisableDeleteNotify = 1 means Windows TRIM commands are disabled and DisableDeleteNotify = 0 means Windows TRIM commands are enabled.
      3) I'm not sure, but I would think that as long as Mozy can access the drive and copy the data from it, encryption shouldn't matter - it's still just data.

  9. Gregory Standforth
    June 5, 2014 at 4:22 am

    Truly, securely sanitizing an SSD _cannot_ yet be done. But these people are working on it:

    http://nvsl.ucsd.edu/index.php?path=projects/sanitize

    • Guy M
      June 5, 2014 at 5:54 pm

      Very interesting resource! These guys are way smarter than me. I get the general concept, but the fine details are beyond my patience.

  10. Javier Claussell
    June 5, 2014 at 3:33 am

    i use the cipher/ c: command prompt. time consuming but works fine.

    • Guy M
      June 5, 2014 at 12:13 pm

      CIPHER /W:C: would do a better job as it removes data from unused disk space.

      Plain old CIPHER /C: just encrypts the data. It doesn't get rid of it. Encryption is still terribly important so it's good to do anyway!

      Be careful with the CIPHER /W command though - it can delete entire volumes.

  11. pmshah
    June 5, 2014 at 3:26 am

    There is also another simple and fast method to do the same. Or at least logic says it should.

    There are a few freeware utilities that will either erase or write FF for every byte that is not allotted to any file. After running this utility I defrag the volume. Once this completes I run the utility once. Logically one should not be able to get any thing decent from erased file areas ! The whole process is very fast too.

    • Guy M
      June 5, 2014 at 12:14 pm

      That would do the trick for most people. Nice! I love getting these sort of tips from our readers.

  12. Haley Q
    June 5, 2014 at 1:36 am

    Ok, I didn't know all these but still this is scary if anyone can recover any of the files.
    Maybe the next time I will dump my HDD from top building down. If that actually works to destroy every bits of it.

    • Guy M
      June 5, 2014 at 1:45 am

      Nothing to be really scared of. Follow the steps for Most Secure Method and you'll most likely have nothing to worry about. Unless you're a high value target like a billionaire or a celebrity.

    • pmshah
      June 5, 2014 at 12:39 pm

      I very simply remove the HDD from my PC and get the recipient to buy his own. I have 11 cleaned and wiped HDDs stacked in my secure steel wardrobe !

  13. Godel
    June 5, 2014 at 1:15 am

    With SSDs one option is to delete your files as normal, then shut down Windows but leave your computer powered up for 20 minutes or so.
    This "quiet time" will encourage your SSD's firmware to do a full Trim operation.

    It's not completely secure, but it may be the best you can do without a complete wipe.

    I think CCleaner should add a simple deletion option without overwrite for SSDs. It would still be performing a valuable function of ferreting out all the hidden temp files etc, even if it couldn't guarantee a subsequent data overwrite.

    • Guy M
      June 5, 2014 at 1:42 am

      Cool. I didn't know that!

  14. David Shear
    June 4, 2014 at 9:25 pm

    "low-level-formatting is actually when there is a completely blank disk, and then the formatting into sectors is written onto it. This was possible with pretty old technology drives - but not with modern drives, for many years.

    Drives now are low-level formatted in the factory, and cannot be changed by the user..

    The proper term is "write-to.zeroes" which simply fills all sector data areas with zeroes (or some other pattern". It doesn't touch the sector information.

  15. Rick VanGameren
    June 4, 2014 at 9:02 pm

    If I take that old PC and load up a fresh version of some flavor of Linux, wouldn't that do the job?

    • Guy M
      June 5, 2014 at 1:41 am

      Yes and no. Depends how securely you want the data deleted. It would be secure enough for most people. Super spies could possibly recover some of the data though.

    • donespo
      June 9, 2014 at 12:32 pm

      After loading Linux, install and run the application Bleachbit. It has the option to do multiple wipes if you'e especially paranoid. I've repurposed several older Windows boxes for friends and family and use this method as a matter of course now. Be prepared to wait a while if the drive is large though. I run it overnight whenever possible.

  16. g.m.nelson
    June 4, 2014 at 8:36 pm

    by the way DoD stands for the U.S. Department of Defense not British.

    • Guy M
      June 5, 2014 at 1:40 am

      Ah. Must be my Canadianess shining through. I forgot that the Brits call it the M.o.D.

  17. Joe M
    June 4, 2014 at 7:43 pm

    I don't know how secure it is, but after deleting the file(s) I just do a defrag

    • g.m.nelson
      June 4, 2014 at 8:43 pm

      if the file you delete is anywhere in the middle of the data on the disk it would be good, the only problem is if the file is at the very end of the used space and is not overwritten during the file moves, then it could possibly still be recovered.

  18. Bryan P
    June 4, 2014 at 6:17 pm

    I'm a Windows command line freak. So I use sdelete from Sysinternals. It can securely delete files, and it can completely wipe free space.

    On FAT32 disks, I wrote a utility that would zero out the data in a file, including the empty space in the last cluster. I would then truncate the file to zero bytes, to make sure the directory entry wouldn't show the file size, and then zero the file attributes, date and time, to make sure that nobody would know what time the file was last accessed, and then rename the file to a one character file name, no extension. When MS-DOS would mark the file as deleted by making the first character E0, it would effectively wipe the file name off the hard drive.

    wipe -fr c:* was quite dangerous and thorough.

    I couldn't find much that would help me do much with subdirectories, unfortunately. I don't think that I even renamed them before doing the rmdir. I think with what I did with the files, unless the directories were quite descriptive, there wouldn't be anything recoverable, anyway. And I lost the source some time ago. :(

    But with NTFS, that would never work. Besides which, I ran into sdelete, so I decided I didn't have to write it.

    • Guy M
      June 4, 2014 at 6:23 pm

      Nice. I don't know what I would do with SysInternals Suite. I hope Russinovich and Cogwell got seriously paid when they merged with Microsoft. Great work.

    • pmshah
      June 5, 2014 at 12:47 pm

      There is a freeware version of Take Command by JPSoft. If you use the global option it can recurse each and every directory regardless of the depth and attributes and run the command that you have specified. Believe I have been their fan ever since I came across Norton Ndos / 4Dos and and 4NT. Simply can't live without it.

  19. Howard B
    June 4, 2014 at 5:54 pm

    Subject line of the newsletter e-mail: "Deletes Files Can Be Recovered By Strangers! ..." Whaaaa????

    • Guy M
      June 4, 2014 at 6:21 pm

      Our newsletter?

    • Mark Hansen
      June 5, 2014 at 1:10 am

      Yes, Guy. It made no sense :p

    • Guy M
      June 5, 2014 at 1:46 am

      Well it did catch your attention. And it's true. Maybe to probable but definitely possible.

    • Howard B
      June 5, 2014 at 6:58 pm

      Not the point; the first word should have been "Deleted", not "Deletes."

  20. Doug
    June 4, 2014 at 3:54 pm

    What about just re-saving the file, with nothing in it? You have a note.txt, with your ss# on it. You want to delete it, permanently. Wouldnt the best way be to simply open the file, erase the ss#, type in asdfasdfasdf, and re-save?

    • Guy M
      June 4, 2014 at 4:05 pm

      Not necessarily. Sometimes applications (like MS Word) have a sort-of auto-version capability which may retain a version with the SSN on the drive, even though you can't find it easily.

      The drive may write the file with the bogus data to a completely different block or page on the drive than the old version of the file - so both could exist simultaneously.

      It's also tedious to do that every time you want to be rid of a piece of sensitive information. Most people won't bother to do that.

  21. James V
    June 4, 2014 at 3:12 pm

    I take them apart and use the magnets, which are REALLY strong. I got a cheap torx bit set from Harbor freight for the purpose. Give the platters a little sandpaper and bending, just to make sure.

    • Guy M
      June 4, 2014 at 4:01 pm

      So you and Al are a bit more in the paranoid column then? ;)

    • James V
      June 4, 2014 at 6:19 pm

      Most of them are dead or real small, but I did get some from the military lab where I worked. Talk about paranoid. ...

  22. Al
    June 4, 2014 at 2:22 pm

    At least for hard drives, my practice is to use a 3/8" drill and drill 4 holes through (all) the platters as well as smash the circuit board on the drive. I think anyone who wants to recover info off that drive is going to need some sophisticated equipment.

  23. Tom P.
    June 4, 2014 at 12:24 pm

    Very useful information. It is such a pain to get rid of an old computer these days. You're constantly wondering whether evil folks are prowling the local dumps looking for all your financial, etc. data.

    • Guy M
      June 4, 2014 at 12:58 pm

      Thank you, Tom. Yes, there are people that do exactly that.

      I used to drive around on the night before garbage pick-up looking for old computers so I could salvage electronics parts for projects. I never thought to go into the hard drives for information, but almost every computer I got still had an accessible hard drive in it, with data on it. It was kind of scary!

      I'd wipe them of course, being the noble person that I am.

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