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How to completely delete the deleted files and programs?

  1. Apr 22, 2015 #1
    I am returning a defective computer, I uninstalled all my installed programs and deleted all the files I put into the computer. I empty the recycle bin. I went into the program files folder and deleted my installed files. Is everything completely deleted?( I don't think so.). What else can I do to delete the stuffs?

  2. jcsd
  3. Apr 22, 2015 #2
    no your files are not deleted

    In order to save time what happens when windows "Deletes" a file, it simply removes that files entry from the disk meta data. Essentially marks the space where those files were as being "free"

    for sensitive files you want to use: https://technet.microsoft.com/en-us/sysinternals/bb897443.aspx

    This tool in addition to marking the space as being free it also writes over the space multiple times to make it much less likely that stuff can be recovered.
  4. Apr 22, 2015 #3
    Also you could reformat the disk if you don't mind having to reinstall the OS.
    That would also cure the other 'defects' if they are arising due to a messed up registry or some other software based cause.
  5. Apr 22, 2015 #4
    You still need to be careful this route, when you reformat a disk if you pick the quick option it does the same thing. Just clears out the meta data, but the information in the files is still there and can be recovered by someone who is invested enough in doing so.
    You can do a bit level (I think thats what its called) format which actually writes over every bit on the drive (sets them all to 0 or 1).

    My family asked me to recycle a couple old computers and were shocked when I pulled out the hard drives and broke the platters. You never know where the recycled material goes and a broken platter is pretty much impossible to recover data from =D I just wanted an excuse to hit stuff with a hammer though lol
  6. Apr 22, 2015 #5
    True, if you go that route, don't use the 'quick format' option, do the standard 'full format' or whatever it's called these days.
  7. Apr 22, 2015 #6
  8. Apr 22, 2015 #7


    Staff: Mentor

    I used the "quick delete" process, using an electric drill to drill holes all the way through all platters on the hard drive.
  9. Apr 22, 2015 #8

    I downloaded it, I ran it. Just a quick flash of DOS and no more action. Is that completed? I did it twice.

  10. Apr 22, 2015 #9

    Vanadium 50

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    Once you breach the casing, putting it in a bucket of soapy water does the trick too.
  11. Apr 23, 2015 #10

    What you'll need to do is the following:
    1) put the sdelete.exe in c:\windows\system32

    2) Locate the directory of the file you want to delete. For example c:\users\dave\documents\bankPasswords.txt
    3) Open a command prompt on Win 7 click the start button and type cmd in the search bar and open cmd.exe
    on xp start->run cmd.exe
    win 8 if you have a start menu installed same as win 7. If you don't. I actually dont know :D

    4) in the command prompt goto the directory that has the file you want to delete by typing:
    cd c:\users\dave\documents (or whatever the directory was from 2)

    5) type sdelete -p 5 bankPasswords.txt (or whatever filename)

    this will delete the file and then write random stuff over the disk space 5 times

    Repeat for all the files you wish to remove
  12. Apr 30, 2015 #11
    Secure deletion utility Eraser is free, comes with a beautiful GUI, can do just about anything when it comes to secure file wiping
  13. May 1, 2015 #12


    So if I already put them in the recycle bin, then I just point to the recycle bin? Also, I already empty the recycle bin. Is it too late?
  14. May 2, 2015 #13
    If you've emptied the recycle-bin, then the data is in "free space".
    "sdelete" has an option to "Clean free space" ... https://technet.microsoft.com/en-us/sysinternals/bb897443.aspx
    which overwrites the data in free space, thus obliterating it. It could take tens of minutes to clean free-space : the process [repeatedly] writing what could be tens of gigabytes of memory on the hard-drive.
    Last edited: May 2, 2015
  15. May 3, 2015 #14
    If you are using Windows there's a free program called Recuva , which will show you what 'deleted' files can be recovered from the recycle-bin portion of "free space".
    You can then select to overwrite particular 'deleted' files found in recycle-bin using Recuva, which is a lot quicker than cleaning all "free space".
  16. May 3, 2015 #15


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    Reading this sounds like a problem purchase from a shop is getting returned for warranty swap etc .... please clarify

    if so, then many of the suggestions that were given for doing physical damage is a real bad idea ... its going to negate warranty etc real quick

    in which case cspcdave's and Bob-A are great advice

  17. May 3, 2015 #16
    Thank you, Dave, for raising that. To the OP, are you returning a defective computer in exchange for a new one? What exactly is wrong with the current computer? If it is isn't the HDD, then can't that be swapped into the new one?
  18. May 3, 2015 #17


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    This is my method for preventing data retrieval.


    I do not recommend this technique if you are planning on returning the computer.
  19. May 4, 2015 #18
    "I swear that nail was there when I bought it"
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