Securely Deleting Data Using Eraser 6.0
Step 1
Download and install the latest stable
version of Eraser 6.0 from eraser.heidi.ie, accepting the default settings.
Unlike with the DiskDigger undeletion utility, there are no concerns about
overwriting data here; you can download it and install it to any convenient
drive, including your main hard disk.
Download
and install the latest stable version of Eraser 6.0 from eraser.heidi.ie,
accepting the default settings.
Step 2
Run Eraser 6.0 and you'll see an empty
Erase Schedule. We're going to manually delete a file, though, so select New
Task from the Erase Schedule menu. This will display the Task Properties
dialog; ensure Run Manually is selected as the Task Type. Click Add Data to
display the 'Select Data to Erase' dialog.
Run
Eraser 6.0 and you'll see an empty Erase Schedule
Step 3
Make sure File is selected, then click
Browse to find the data KM you want to delete and press Ok. Note that we're
choosing to delete the photo of a sign carrying the words 'Keep Out’. Click
Open (a misnomer), then Ok and Ok again. Finally, right-click the file in the
Erase Schedule menu and select Run now.
Make
sure File is selected, then click Browse to find the data KM you want to delete
and press Ok.
Step 4
The file will now be deleted without trace.
Close Eraser 6.0. Just to prove the data isn’t recoverable, we tried to unearth
the file using DiskDigger (see page 84). Try as we might, though, even when
using the Dig Deeper option the software was unable to recover our securely
deleted photo.
The
file will now be deleted without trace
Destroying Optical Media
Optical discs, such as CDs, DVDs and
Blu-rays, are rather different from magnetic or flash drives and most secure-deletion
products won't touch them. For rewritable discs this really isn't an issue,
since you're not going to be disposing of them along with your computer as you
would with the hard drive. If you do decide to give an optical disc to someone,
it's usually because you want to share with them some data.
Destroying
Optical Media
However, write-once discs such as CD-R,
DVD-R and DVD+R tend to be thrown away once you've finished with them. In this
case, the only way you can prevent your data falling into the wrong hands is to
physically destroy the disc. You can buy paper shredders that also shred
optical discs and, if you're paranoid about your data security, that may be an
ideal solution. However, in our experience, low-cost home shredders aren’t
tough enough for this sort of treatment, and shredding CDs on a regular basis
will probably contribute to their premature failure.
No-one is going to spend a fortune on
bleeding-edge data-recovery technology on the off-chance that a CD-R they found
in your bin contains something valuable; just ensuring that it’s in two pieces
will be enough. Cutting it with scissors (not your best pair, mind) is one
option, or you could just snap it in two, having first wrapped it in a cloth to
protect yourself from flying shards of plastic.
Destroying Hard Disks
We've seen that data can be effectively
deleted from a hard disk using nothing more than a secure-deletion utility.
However, if you take the view that anything less than physically destroying the
hard drive isn't good enough, here are a few suggestions.
Destroying
Hard Disks
Bear in mind that we’re not recommending
the methods discussed here (there's really no need) and they all carry the risk
of injury. Remember that some disks contain glass platters, which could shatter
and cut you. If your computer no longer has any value to you, it’s also
possible that a charity could benefit from it. With these caveats in mind,
let's get on to the fun stuff.
When you remove a disk from a PC, the most
easily accessible part will be the circuit board on the bottom; as such, the
easiest way to abuse the drive would be to get to work on that board with a
hammer and chisel. But while that might be the simplest approach, your attempts
would be futile. This isn't where the data is stored. If someone were to
replace that board, they'd still be able to read your data. Instead, any
attempt at destroying a disk should concentrate on the platter or platters -
the silver disk(s) that you'll see when you remove the screws (some of which
may be hidden under labels, and use security heads) and take the drive apart.
Just scratching the platter(s) with a
screwdriver will suffice, even though it's not a particularly satisfying
experience. If you really want to release that pent-up energy, a sledgehammer
would be sure to do the trick. If, on the other hand, you consider yourself
something of a pyromaniac, a conflagration will also ensure that your data
never sees the light of day again - heating up the platters to a red glow with
a blow torch would be ideal, as would dropping it into the heart of a garden
fire. If you have an angle grinder to hand, you may find it rather effective in
drive destruction, too.
These are just a few of our favourites, but
all that stands between you and an exciting way to wipe your data from the face
of the earth is your imagination.
Encrypting Data
None of the methods we've seen thus far
will prevent your data from falling into the wrong hands if your computer is
stolen.
Encrypting
Data
Although it's not directly related to the main
theme of this feature, it's worth encrypting your sensitive files if you’re
worried about possible theft. Turn to page 114 to find out how.
