privacy issue

[scylla]

After I purchase my next computer I intend to either give away or sell my old one. Is there a way to ensure any personal info left on the HD is'nt available? I've been told by some the only way for complete security is to destroy the hd. That seems a waste of a perfectly good comp. thanx

[david eaton]

To be certain that the information on your old computer cannot be read, then yes, destroying the hard drive is the only way!
In reality, there are applications that can delete everything by writing over the disc with random characters several times. These applications can defeat most attempts to read the old info. Try googling for Data deletion to find a program that suits you.

[Sylvander]

I agree that destroying a good HDD is a terrible waste, and practically unnecessary.
Who is going to think it worth their while to spend huge amounts of time and money to try [and almost certainly fail] to recover the contents of the HDD of "li'l ole you".

ERASER (http://www.tolvanen.com/eraser/) is a GREAT [Free] program that complements the "Delete" facility really well.

Within Windows you can use it to write anything up to 35 passes of random 0's and 1's [US Department of Defence only requires 7 passes to protect National Security].
You can use it to irrecoverably "Erase" chosen folders or files, and/or "Erase Unused Space" on partitions/drives.
If you don't want to irrecoverably erase the contents of the whole HDD, and want to leave some stuff on the HDD...
It would be essential to erase the "unused space", because there will be "Deleted" data on the drive in that space that can be recovered unless you use Eraser [or something similar] on it.

The tiny risk with leaving some files on the HDD is that the data previously occupying those used regions would probably be theoretically recoverable [not so practically impossible as those regions having multiple passes written].

Safer to write multiple zeros to the whole HDD.
The "Eraser" program will make "Darik's Boot & Nuke Disk" [a bootable floppy], and that will fill the whole HDD with [a chosen number of] multiple patterns.

You could then, if you wished and if you had the means, restore a backup of the chosen contents of a partition [files and folders only, not an image backup].
So you'd be writing "safe" files to an irrecoverably erased HDD.

If you're not too concerned by the level of irrecoverability, you could write a single set of zeros in much less time using the [FREE] KILLDISK (http://www.killdisk.com/downloadfree.htm).

[mjc]

For the most part, when looking at prices of data recovery...upwards of a $1000 for simple stuff, what would be needed to be used to recover from even a simple 'wipe' (single pass zero fill) would probably push that figure above $10,000...by the time a 35 pass random fill/wipe is done, even the FBI would balk at the price tag...unless you are involved in trading national secrets or something.

For general use, a simple full zero-fill/wipe is enough. In fact, that followed by an install will defeat most attempts at recovering anything (if it doesn't involve national security). A full 35 pass wipe makes it nearly impossible to recover anything, unless using some very expensive, very sophisticated equipment that approaches SciFi levels of technological 'magic', likely only to be owned by Alphabet-soup US government agencies (price tag on hardware....tens of millions of dollars).

And no, the time, effort, hardware needed push this type of thing well beyond what someone (even a die hard 'hacker') can accomplish at home...

[johnny_quest]

hooray for paranoia!

actually, anytime i find a computer in the trash, i always see what's on the old harddrive. Never to do anything illegal, but just to satisfy my own curiosity :)

[scylla]

So how secure is a simple reformat by either norton ghost or my install cd? I'm just worried about the average joe coming across my credit card # or pics of Ms Spears on my desktop. I use my laptop for the pursuit of the rabbitsfoot.:D

[Sylvander]

Do you mean a repartition of the HDD followed by a reformat of the partitions, or just a reformat of existing partitions?

I'm no expert, but I expect a reformat is not secure at all.
The bootable EBCD ["Emergency Boot CD"] has [among its many other programs] the "Un-Format" and "Un-Erase" [actually it should say "Un-Delete"] programs.
I've never used the Un-Format program.
Used the Un-Erase program, and any file that has been deleted and by-passed the Recycle Bin, but hasn't had any of [the (perhaps non-contiguous) parts of] its files overwritten, can be recovered with ease.
Sometimes some [non-contiguous] parts of a file have been overwritten and the program has these marked as not fully recoverable.

During a reformat of a partition, or delete of folders and/or files, nothing of the folders or files have been eliminated.
In the case of a reformat the file tables specifying the location of the files have had the settings removed, but the files are still in place.
In the case of a delete, the file settings in the file table have been marked as available for use, but the files are still in place.

[PrntRhd]

Eraser would be first choice,
DBAN (Darricks Boot and Nuke) second,
the HDD manufacturer utility to "wipe" the drive third choice.

Sylvander:
During a reformat of a partition, or delete of folders and/or files, nothing of the folders or files have been eliminated.
In the case of a reformat the file tables specifying the location of the files have had the settings removed, but the files are still in place.
In the case of a delete, the file settings in the file table have been marked as available for use, but the files are still in place.
Exactly, the files are there and are recoverable.

[mjc]

The way I would do it is use Eraser to clear out all personal data while in Windows, then boot to the DBAN disk and wipe the drive with it, followed by a repartition/format.

If the machine was a major brand and has a set of restore disks, the final thing I would do would be to run them. Remember, the 'proper' way to pass on a system with restore disks is to pass the restore disks with it.

If it doesn't have a restore set and had a retail version of Windows, I would install some version of Linux on it before passing it on...