How Can I Be Sure I've Deleted All My Data ?

  • 35 Replies
  • 11232 Views

0 Members and 1 Guest are viewing this topic.

*

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • 20602
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« on: 03/03/2011 12:31:32 »
I'm about to throw away/recycle an old laptop !...I'm in the process of deleting/cleaning everything I can off it. I do know that although data seems to be deleted it is still retrievable yes ?

Why is that ? ...and besides smashing it ..is there a way to guarantee deletion of all data ?..strong magnet ?




Ta

Men are the same as women, just inside out !

*

Offline RD

  • Neilep Level Member
  • ******
  • 8185
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #1 on: 03/03/2011 12:58:35 »
The people who make CCleaner also make a free program called Recuva, which shows files which have been put in the trash but have not been overwritten so can be recovered. Recuva also has the option to securely overwrite any found files. Recova gives the option to overwrite 1, 3, 7 or 35 times, but one overwrite is sufficient.

http://en.wikipedia.org/wiki/Recuva

[I've assumed you’re using a Windows OS]

BTW If you are planning on recycling or re-selling the computer note that if you do manage to alter the hard drive with a magnet it will render it unusable: as it will also delete magnetic information which guides which position the hard drives's read/write head. 
« Last Edit: 03/03/2011 13:47:02 by RD »

*

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • 20602
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #2 on: 03/03/2011 13:08:54 »
The people who make CCleaner also make a free program called Recuva, which shows files which have been put in the trash but have not been overwritten so can be recovered. Recuva also has the option to securely overwrite any found files.

http://en.wikipedia.org/wiki/Recuva

[I've assumed you’re using a Windows OS]


Thanks RD...yes..It's windows XP...thing is....no connection to the internet on it....so I can't download anything to it. I does have CCleaner on it and I've been using it to uninstall and wipe away as much stuff as I can. I've manually deleted all documents and pictures but I gather they are still on there really eh ?...it has a floppy drive !!...it's a 2002 Dell !

Men are the same as women, just inside out !

*

Offline RD

  • Neilep Level Member
  • ******
  • 8185
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #3 on: 03/03/2011 13:27:29 »
.It's windows XP...thing is....no connection to the internet on it....so I can't download anything to it.

You could download Recuva from the computer you are using now onto a USB stick, then transfer it to your old PC that way ...

Apparently Recuva will run on XP ...

[attachment=14082]

If you click this link ... http://www.piriform.com/recuva/download/standard
You should see this ...

[attachment=14084]

Choose to save the file (not run) to your computer then transfer a copy of the "rcsetup139.exe" file to your old (XP) computer via a USB stick, (or via CD / DVD ), then you should be able to run Recuva on your old XP computer.
« Last Edit: 03/03/2011 13:37:29 by RD »

*

Offline RD

  • Neilep Level Member
  • ******
  • 8185
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #4 on: 03/03/2011 14:18:15 »
If you have the latest (V3) version of CCleaner it has a "drive wiper" which will securely overwrite the "free space" which is where deleted but possibly recoverable files reside ...

[attachment=14088]

NB: just wipe the “free space”.
If you select to wipe the “entire drive” on the drive which includes the Operating System, (XP, Vista etc), the computer will make an unrecoverable crash at some point during this process when it overwrites the software necessesary to perform overwrite.

You will then have to reinstall the Operating System to make this computer usable, (a reinstall from DVDs or external hard drive, NOT from  a back-up copy of the OS on the computer: it would be wiped), i.e. a “bare metal” reinstall would be required.
« Last Edit: 03/03/2011 17:44:15 by RD »

*

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • 20602
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #5 on: 03/03/2011 17:10:58 »
Thanks RD...that's simply super info......My USB drive keeps shorting the computer out when I plug a card into it so I will burn a cd and hope the cd player still works !...The Dell has had it's full measure. Unfortunately I have an older version of CCleaner so no 'drive wiper'!

Will report back when all is done.

Thanks again

Men are the same as women, just inside out !

*

Offline RD

  • Neilep Level Member
  • ******
  • 8185
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #6 on: 03/03/2011 17:21:23 »
... I will burn a cd and hope the cd player still works !...The Dell has had it's full measure. Unfortunately I have an older version of CCleaner so no 'drive wiper'

You could transfer the latest version of CCleaner, with "drive wiper", at the same time you transfer Recuva (via CD).

Possible method ...

1. Put your files in the trash (recycle bin), e.g. select all, (“Ctrl” + “A”), documents/pictures/music etc then hit delete.
2. Optional. If you run Recuva at this point you can see that the deleted files can be recovered from trash.
3*. Run CCleaner’s drive wiper to wipe “free space only”, (this may take 10s of minutes to complete).
4. Run Recuva (again) to check that there are no recoverable deleted files.

* be absolutely sure you don't need these files, (e.g. you have back up copies), as they cannot be recovered after step 3 is complete.
« Last Edit: 03/03/2011 18:48:10 by RD »

*

Offline SeanB

  • Neilep Level Member
  • ******
  • 1118
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #7 on: 03/03/2011 18:24:25 »
Google DBAN ( www.dban.org ) and burn the ISO to a cd, and boot from it. Will wipe the drive clean very easily, and then you can use the install media to reinstall XP as it was when you bought it.


*

Offline RD

  • Neilep Level Member
  • ******
  • 8185
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #8 on: 03/03/2011 18:41:17 »
... you can use the install media to reinstall XP as it was when you bought it.

If you have all the reinstall disks, (including the one which creates the Dell partitions before you intall the OS), and you are willing and able to download years worth of XP updates from the internet, and up to date Dell drivers, and reinstall any other software currently on the computer, (e.g. word processor, speadsheet, etc).

I do agree that wiping the entire hard drive and reinstalling the OS is the most secure option.
Certainly if the computer (or just its hard drive) is being binned, rather than reused or sold, then DBAN is the way to go.
« Last Edit: 03/03/2011 18:55:33 by RD »

*

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • 20602
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #9 on: 03/03/2011 19:10:40 »
Thank ewe both RD and SeanB. I will consider all these options.

Fact is, it's such an ancient laptop that I was going to donate it to my kids school but it runs so slowly that there really is no use for it ...so...my final idea was to scrap it.....so...perhaps using the DBAN is best for me....I truly can not see anybody getting any use from it........

THANK YOU VERY MUCH  [:)]
Men are the same as women, just inside out !

*

Offline RD

  • Neilep Level Member
  • ******
  • 8185
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #10 on: 03/03/2011 19:43:10 »
Fact is, it's such an ancient laptop that I was going to donate it to my kids school

You could run CCleaner and Recuva as I have suggested (including the optional step 2),
Then you could be confident your deleted files were gone and could no longer be recuva'd.

Then you could run DBAN (this is overkill) which would wipe everything from the hard drive including the OS.

Then you could give the computer to the school (or other recycle option) where a geeky person could install the XP OS from your install disk if you still have it, or they could install a Linux OS which is free …


Quote
London-based Computer Recycling Specialists

We use data-wiping software on disks that are re-used and reload a new Operating System, rendering recovery of previous data impossible.
http://www.recycle-it.co.uk/

« Last Edit: 03/03/2011 20:15:55 by RD »

*

Offline Bored chemist

  • Neilep Level Member
  • ******
  • 8848
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #11 on: 04/03/2011 07:06:10 »
If the thing isn't doing anything useful then fit a webcam to it and get it to record a video of the wall until the disk is full.
Then you know exactly what data is on it, and if anyone finds it, who cares?
Please disregard all previous signatures.

*

Offline Pumblechook

  • Hero Member
  • *****
  • 569
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #12 on: 04/03/2011 12:01:50 »
I am not sure a magnet will do anything to a hard drive.  Aren't they screened with magnetic material?  At least a steel case if not mu-metal.   I have have removed hard drives form PCs and smashed them up with a big hammer... great fun.

*

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • 20602
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #13 on: 04/03/2011 12:43:35 »
I really like the idea of the webcam but as I have discovered my usb sockets are dead.....I tried plugging something into them but they shorted the laptop....I can see inside that an insulated edge has come off !............now...the thing won't even turn on yet the light to indicate the battery is charging is working !!


I have a feeling it's going to be:


[attachment=14094]


Hammer Time !!




Thank you all again for your kind advice and guidelines. The information supplied will help me in the future too so despite this laptop quitting the Earth in this particular way I have found this thread to be a worthwhile exercise !..


TA !!
Men are the same as women, just inside out !

*

Offline imatfaal

  • Neilep Level Member
  • ******
  • 2787
  • rouge moderator
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #14 on: 04/03/2011 13:54:41 »
The remains of my last couple of harddrives - theyre prettier than cd, but don't stop the heat

[attachment=14096]
There’s no sense in being precise when you don’t even know what you’re talking about.  John Von Neumann

At the surface, we may appear as intellects, helpful people, friendly staff or protectors of the interwebs. Deep down inside, we're all trolls. CaptainPanic @ sf.n

*

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • 20602
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #15 on: 04/03/2011 14:07:01 »
The remains of my last couple of harddrives - theyre prettier than cd, but don't stop the heat

[attachment=14096]


very nice !!


Having just smashified mine they were in too poor a state to salvage.....*le sigh*
Men are the same as women, just inside out !

*

Offline SeanB

  • Neilep Level Member
  • ******
  • 1118
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #16 on: 04/03/2011 15:05:59 »
If it is old and slow, then the best will be to download a copy of Ubuntu, Debian or some other Linux disro and install it on the computer. You can use the installer to wipe the drive as it installs ( not a secure wipe but will still make it difficult to recover data later) and then use it to surf the web. If you use Puppy linux you can remove the hard drive and boot and run off a USB stick, or install it to the drive and have a very fast laptop again, with a large amount of storage again.

*

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • 20602
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #17 on: 04/03/2011 15:44:59 »
If it is old and slow, then the best will be to download a copy of Ubuntu, Debian or some other Linux disro and install it on the computer. You can use the installer to wipe the drive as it installs ( not a secure wipe but will still make it difficult to recover data later) and then use it to surf the web. If you use Puppy linux you can remove the hard drive and boot and run off a USB stick, or install it to the drive and have a very fast laptop again, with a large amount of storage again.

Thanks for that very useful info Seanb......however, the computer is now an EX-PUTER..it has ceased to be !!   [;)]
Men are the same as women, just inside out !


*

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • 20602
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #19 on: 04/03/2011 18:08:01 »
Be absolutely sure...

http://www.diytools.co.uk/diy/Main/sp-53-5230-91345-sealey-cut-off-machine-355mm-230v-portable.asp


awwww....thanks Pumblechook !!..when can i expect delivery ?  [;)]


...actually...i was thinking about getting my drill out but.....well...I just continued hammering !!
Men are the same as women, just inside out !

*

Offline Pumblechook

  • Hero Member
  • *****
  • 569
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #20 on: 05/03/2011 10:12:28 »
A cheap angle grinder would do but you must wear googles.  I learnt the hard way.

*

Offline SeanB

  • Neilep Level Member
  • ******
  • 1118
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #21 on: 05/03/2011 11:37:20 »
Just remember that Lithium batteries are not the best thing to bash open, as they tend to go out with a final farewell fireworks and pyrotechnic display.

*

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • 12342
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #22 on: 05/03/2011 14:43:21 »
I've read tests where they stated that you could recover data over written seven times. The military have one way to treat old HD as I know and that is Neils hammer. That said you can use electromagnets to wipe data, but they have to be strong. Take a look here but they seem to fall back on a hammer too. "A force field of 10.000 Gauss or one Tesla is necessary to erase the drive." But if you're looking for the opposite, and you should, it's all to easy to have your HD lose info by playing with different OS, and other crashes, then I would recommend 'Ontrack "easyrecovery profesional 6.21" it works as good as anything outside the professional data recovery business you ever will find.

I've found it very useful at occasions. Maybe there are something better out there but I doubt it, I looked extensively before choosing that one.

Simply erasing all the data on your hard drive and formatting it is not enough security. using the delete key on your keyboard in Windows only removes the shortcuts to the files. Deleted files will still reside on the hard drive making them very easy to recover. Formatting your hard drive better than simply erasing the files. Formatting a disk does not erase the data on the disk, only the address tables. If you have decided a disk format is a good choice, do a full format rather than a quick format. Then you can use disk wiping which process will overwrite your entire hard drive with new data, several times. A simple way of doing it manually is to use a Linux OS then reformat your Hard drive into some different layouts, like DOS then NT then some Linux and use 'full/slow format' all three times, with error checking, which will force the software to write a 'one' to all 'bits' on your Hard drive, to then lift it up again to see if it can read it. Do it with three different OS tables and it should be quite difficult to recover. And it's as fast as anything else on the market I guess.

Here is some wiping software if you just want to wipe certain files. Wiping I would expect Darik's Boot and Nuke and Sysinternals to be good at cleaning out your HD, but, the best is your hammer/shredder :)

« Last Edit: 05/03/2011 14:46:35 by yor_on »
"BOMB DISPOSAL EXPERT. If you see me running, try to keep up."

*

Offline RD

  • Neilep Level Member
  • ******
  • 8185
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #23 on: 05/03/2011 16:17:50 »
A cheap angle grinder would do but you must wear googles.  I learnt the hard way.

I think I caught your act  [:)] ... http://www.youtube.com/watch?v=6VJHyCR9gXs#t=2m5s

*

Offline Bored chemist

  • Neilep Level Member
  • ******
  • 8848
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #24 on: 05/03/2011 20:32:01 »
Whatever tickles your fancy I guess.
Tell me RD, what were you looking for when you found that?
Please disregard all previous signatures.

*

Offline RD

  • Neilep Level Member
  • ******
  • 8185
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #25 on: 05/03/2011 21:11:04 »
Whatever tickles your fancy I guess.
Tell me RD, what were you looking for when you found that?

Applying an angle grinder to the nether regions is actually old hat as performance art, so there are many examples on Youtube, e.g. ... http://www.youtube.com/watch?v=fScLtevPUBU
http://www.youtube.com/watch?v=GhdUKiRX2iI

[Don’t try this at home, unless you’re wearing a chastity belt and have lost the key ]
« Last Edit: 05/03/2011 21:22:58 by RD »

*

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • 20602
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #26 on: 06/03/2011 16:12:00 »
I've read tests where they stated that you could recover data over written seven times. The military have one way to treat old HD as I know and that is Neils hammer. That said you can use electromagnets to wipe data, but they have to be strong. Take a look here but they seem to fall back on a hammer too. "A force field of 10.000 Gauss or one Tesla is necessary to erase the drive." But if you're looking for the opposite, and you should, it's all to easy to have your HD lose info by playing with different OS, and other crashes, then I would recommend 'Ontrack "easyrecovery profesional 6.21" it works as good as anything outside the professional data recovery business you ever will find.

I've found it very useful at occasions. Maybe there are something better out there but I doubt it, I looked extensively before choosing that one.

Simply erasing all the data on your hard drive and formatting it is not enough security. using the delete key on your keyboard in Windows only removes the shortcuts to the files. Deleted files will still reside on the hard drive making them very easy to recover. Formatting your hard drive better than simply erasing the files. Formatting a disk does not erase the data on the disk, only the address tables. If you have decided a disk format is a good choice, do a full format rather than a quick format. Then you can use disk wiping which process will overwrite your entire hard drive with new data, several times. A simple way of doing it manually is to use a Linux OS then reformat your Hard drive into some different layouts, like DOS then NT then some Linux and use 'full/slow format' all three times, with error checking, which will force the software to write a 'one' to all 'bits' on your Hard drive, to then lift it up again to see if it can read it. Do it with three different OS tables and it should be quite difficult to recover. And it's as fast as anything else on the market I guess.

Here is some wiping software if you just want to wipe certain files. Wiping I would expect Darik's Boot and Nuke and Sysinternals to be good at cleaning out your HD, but, the best is your hammer/shredder :)



Thank You also yor_on for your very insightful knowledge and software links.

I could attempt all this but I would need to put my hard drives back together now...as well as the laptop .

The information you have given though is not wasted and thoroughly appreciated !
Men are the same as women, just inside out !

*

Offline Geezer

  • Neilep Level Member
  • ******
  • 8328
  • "Vive la résistance!"
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #27 on: 06/03/2011 19:35:57 »
If you want to erase the data from a disk platter without actually destroying it, I'd suggest sticking it in the oven on high for half an hour, then, while it is still hot, subject it to a few hundred g's acceleration by whacking it with a mallet a few times.
There ain'ta no sanity clause, and there ain'ta no centrifugal force æther.

*

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • 20602
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #28 on: 06/03/2011 19:38:38 »
If you want to erase the data from a disk platter without actually destroying it, I'd suggest sticking it in the oven on high for half an hour, then, while it is still hot, subject it to a few hundred g's acceleration by whacking it with a mallet a few times.



That's what I do to wifeys apple pie anyway !
Men are the same as women, just inside out !

*

Offline RD

  • Neilep Level Member
  • ******
  • 8185
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #29 on: 06/03/2011 20:07:59 »
If you want to erase the data from a disk platter without actually destroying it, I'd suggest sticking it in the oven on high for half an hour, then, while it is still hot, subject it to a few hundred g's acceleration by whacking it with a mallet a few times.

If your oven goes up to gas mark 36* you won't need to whack it ...

Quote
A magnet will lose its magnetism if heated above the Curie temperature.
The curie temperature of Iron is 770 o C
http://en.wikipedia.org/wiki/Curie_temperature

[* A domestic oven only goes up to about 250 oC]
« Last Edit: 07/03/2011 02:30:39 by RD »

*

Offline CliffordK

  • Neilep Level Member
  • ******
  • 6321
  • Site Moderator
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #30 on: 06/03/2011 23:32:20 »
You might just yank your hard drive and keep it as a backup.

I have a degausser...  Have to take it on faith that it actually wiped the hdds...  But, the drives were unreadable, and likely destroyed so they couldn't be easily reformatted.  Then a sledge does the rest  :)

Any wipedisk program has to boot from floppy/CD.
Actually...  I think the one I used to use was called "WipeDisk".  Put it in "secure mode", and it would chug for about a day or so.  I'm not positive of the exact version I used to have, but it seemed to be effective.

*

Offline Geezer

  • Neilep Level Member
  • ******
  • 8328
  • "Vive la résistance!"
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #31 on: 07/03/2011 05:20:37 »
BTW, rather than wreck your old drives, it's a lot more fun to take them apart. The engineering and manufacturing processes that go into HDs are truly amazing.

I like to recover the magnets from the voicecoil mechanism (that's the bit that makes the heads move from track to track). Watch you fingers though. These are extremely powerful magnets. You may think they are welded to the assembly, but it's only magnetic attraction that is holding them in place.
There ain'ta no sanity clause, and there ain'ta no centrifugal force æther.

*

Offline Madidus_Scientia

  • Neilep Level Member
  • ******
  • 1451
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #32 on: 07/03/2011 16:19:49 »
Haha, bloody disaster waiting to happen

*

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • 20602
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #33 on: 07/03/2011 19:24:15 »
You might just yank your hard drive and keep it as a backup.

I have a degausser...  Have to take it on faith that it actually wiped the hdds...  But, the drives were unreadable, and likely destroyed so they couldn't be easily reformatted.  Then a sledge does the rest  :)

Any wipedisk program has to boot from floppy/CD.
Actually...  I think the one I used to use was called "WipeDisk".  Put it in "secure mode", and it would chug for about a day or so.  I'm not positive of the exact version I used to have, but it seemed to be effective.

Great Information..thank you very much CliffordK
Men are the same as women, just inside out !

*

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • 20602
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #34 on: 07/03/2011 19:32:45 »
BTW, rather than wreck your old drives, it's a lot more fun to take them apart. The engineering and manufacturing processes that go into HDs are truly amazing.

I like to recover the magnets from the voicecoil mechanism (that's the bit that makes the heads move from track to track). Watch you fingers though. These are extremely powerful magnets. You may think they are welded to the assembly, but it's only magnetic attraction that is holding them in place.

Do you know what this is chum ? http://www.thenakedscientists.com/forum/index.php?topic=37754.msg346722#msg346722
Men are the same as women, just inside out !

*

Offline omniphile

  • First timers
  • *
  • 2
    • View Profile
How Can I Be Sure I've Deleted All My Data ?
« Reply #35 on: 07/03/2011 20:29:08 »
Fact is, it's such an ancient laptop that I was going to donate it to my kids school but it runs so slowly that there really is no use for it ...so...my final idea was to scrap it.....so...perhaps using the DBAN is best for me....I truly can not see anybody getting any use from it........

I was in the same position about 12 months ago (it may have even been the same model laptop - a Dell Inspiron 1100). Then one rainy weekend, the 2 kids and I sat down with a set of jeweller's screwdrivers and we dissected it with me pointing out and identifying the various parts of its innards.

They had a great time being permitted to disassemble something (for a change) and really learnt quite a lot from the experience. They also found how useful their magnfying glasses were for studying itsy-bitsy things.

The bonus, of course, is that no terrestial being can possibly repair or recover anything my kids have touched!

Cheers