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Data Recovery Myths and Misconceptions
In the very early 80's, IBM introduced
the IBM PC, progenitor of most modern personal computers.
That same year, undoubtedly, the first PC hard disk failed
and someone was screaming about their data and cursing IBM.
Shortly after that, we started the data recovery industry
and created most of the established practices and recovery
techniques in use today. Over the years we've seen quite
a few pieces of misguided advice about recovering data in
the popular media, and heard many others. I don't know if
we've heard it all, but we've heard these:
Slap it, heat it, hit it, freeze
it, drop it, tap it, swap the board, open it and spin it,
use Norton, spin it with a drill, use a higher voltage,
it will fix itself, and pray.
I'll address a few of those here.
Hit
it and its variations: slap
it, tap it, and
drop it.
Sounds like a substitute for Snap, Crackle, Pop, and their
brother, doesn't it? And surely, the frustration that comes
with a hard drive that won't give it up is enough to make
one want to hit and slap, with maybe a little kick and toss
thrown in. But all of these are bad ideas if you want your
data back. We've seen many variations in user magazines
over the years.
The
problem: The drive won't spin. Older drives had an
issue called, "stiction," a contraction of "stick" (as in,
"stuck") or "static" with "friction." The basic problem
of stiction is that the read/write heads have adhered to
the platters inside, and the motor doesn't have enough torque
to get started spinning. This isn't the only reason drives
don't spin — in fact; it is not the major reason. Modern
drives (those since 1995 or so) almost never get stiction.
The
solution: If your drive actually has stiction, you
might try our patented* "stiction spin." Hold the drive
by opposite corners, parallel to the floor. Imagine a post
coming up from the floor through the center of the drive
(you might have already imagined this!), and rotate the
drive around the axis of that imaginary pole abruptly. In
other words without letting go, spin the drive abruptly
a half turn. Repeat twice. Be careful not to let it go Frisbee-ing
across the room! Now apply power and see if it works. If
it doesn't work, the drive probably does not have stiction
and needs to be sent to a data recovery house.
Heat
it, freeze it:
When a drive won't spin, some have recommended applying
heat with a hair dryer or heat gun, or putting the drive
in the freezer, or both alternately
The
problem: The drive won't spin or there's a circuit
board problem. The idea behind unsticking a drive with heat
or cold is that the contraction or expansion of components
inside a drive will knock the heads loose form the media
so the drive can spin. Unfortunately, both hair dryer &
freezer are pretty bad ideas. While they've been known to
work once in a while, they've been known to destroy the
drive as well. Heating can destroy any number of components
on and in the drive. A freezer can cause moisture to condense
on the platters inside, rendering them further damaged.
The
solution: If the drive has stiction, use the (non)
patented stiction spin, described above in. If the circuit
board has a hot spot, it may be able to be kept cool with
a fan, or occasional application of canned freeze spray
(really), or by holding canned air upside down and spraying.
It's very cold, so don't spray your skin! One of the weaknesses
of using freeze mist is that a) the abrupt intense cooling
can damage an electrical component, and b) your can of cold
stuff will run out in a minute or so. If blowing cool air
with a fan will not keep the drive cool enough, there's
something seriously wrong and you probably need to send
the drive in for recovery.
Swap
the board:
The idea behind this approach is to take the circuit board
from another disk drive and use it on the bad one.
The
problem: Sometimes the first problem a drive has
is the circuit board frying. This can yield a number of
secondary problems, most notably partition and file structure
getting nuked when the board fries. In such a case, a board
replacement will not get the data back, although the drive
may function physically. If other components, such as the
motor, heads, head assembly driver or cabling has shorted,
hooking up another circuit board may simply blow the new
board out.
Still, if there was no file structure
or partition damage, and no internal shorts, this approach
used to work fairly well on older drives, before manufacturers
were making components in different factories all over the
world, before drives gained some internal intelligence,
and before drive sales became so dramatically competitive.
Now drives may differ form week to week, from factory to
factory. In many cases, a board will have to have been manufactured
for the same OEM during the same week or month, at the same
location for components to match and work.
It
will fix itself:
Hey, sometimes just leaving it alone for a while and trying
it again later works. If it works for you, remember the
Boy Scout creed: Be Prepared! Have media standing by to
back up your important data immediately!
Use
a higher voltage:
Don't do it! It will just burn something out.
Spin
it with a drill:
Need I say it? Just don't do it. If the drive is not spinning
fast enough, and even if you could get it spinning at exactly
the right speed with a drill (something I'd like to see...
) spinning it faster won't help. The drive's internal tachometer
and motor electronics are intimately intertwined. Spinning
it externally won't help.
Use
Norton:
There are a number of utilities, including Norton Disk Doctor,
whose purpose it is to repair file structure.
The
problem:
Anything that writes to the drive is overwriting something
already on the drive. If a utility writes the wrong thing,
it can make the problem worse to the point of making the
data unrecoverable. We have seen hundreds of drives in this
condition, so this is not a light warning. Furthermore,
if the problem with the drive is media damage (about 10%
of the time), then the longer it runs, the worse it gets.
A drive can be destroyed within a few minutes once the media
begins to become compromised.
The
solution:
If you must use utility software, try to use something that
does not write to the drive. There are certain errors that
are very likely to cause damageÉin particular trying to
let software repair any error condition with the word "node",
"tree", "branch", "FAT", or "MFT" is quite dangerous. If
the utility lets you save an undo file, it's best to use
that option. If the utility has an option to allow you to
select what repairs to do- select that option. It may take
longer, but its best to keep it from automatically performing
repairs. If you hear any suspicious noises — clicking,
grinding, or erratic spinning, stop!
Open up the drive: Drives are manufactured
under extremely clean environments. You can't get your office
or home clean enough to make it safe to open a drive unless
recovering the data is not important. A small piece of dust
is dozens of times wider than the gap between head and platter
inside the drive, and at 7200 or 10,000 RPM, a piece of
dust packs quite a punch. Even a fingerprint is like a small
mountain at this scale. Furthermore, the insides of the
drive are aerodynamically designed to exacting conditions,
and lifting the lid destroys that environment. Opening the
drive will be interesting, but unlikely to yield any progress
in an office or business environment.
Prayer: Works sometimes too. Still
back up your data! Because the next time you may not have
a prayer!
Call
Data Recovery WorldWide for data recovery services.
This one's not a myth. We can almost always save your data.
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