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When Good Disks Go Bad - Part 2
by Alan German
As noted in Part 1 of this article, the Lost
Partition Recovery and Damaged Partition Recovery modules
of MiniTool’s Power Data Recovery software are
applicable to the partition structure of hard drives.
What we need to test these modules is a hard disk with
either a lost or a damaged partition.
Here is where Jeff Dubois rides his white charger to our
rescue, or – perhaps having tired of flogging two
dead horses – hands over a couple of hard drives for
experimentation. Jeff’s disks had been busy working
in a “Just a Bunch Of Disks” (JBOD) array
before being replaced when they started to make strange
noises.
The individual drives each had a 1 TB capacity but, as
with the SDcard we encountered in Part 1 of this
article, Windows’ File Explorer refused to
acknowledge the existence of any file system on either
disk. Similarly, the Disk Management utility showed each
disk as not being initialized and having 931 GB of
unallocated space.
One of the 1 TB
drives was loaded into an All-in-1 Docking Station which
connected to the computer through a USB port. The Damaged
Partition Recovery module of Power Data Recovery
wasn’t of any help since it didn’t show the
drive in the list of available drives and partitions.
Consequently, the Lost Partition Recovery module was
employed.
The test
disk was selected from the list displayed in this module
and a Full Scan conducted on the hard drive. Given the
large capacity of the drive, the time required for the
scan was of the order of eight hours. Needless to say,
the computer was left to process the drive overnight.
The results of the scan were
somewhat confusing. The recovery software claimed to have
identified 201 disk partitions. Now, even though this
disk had been in use for some time, it seems highly
unlikely that it had ever contained 200 individual
partitions. Even stranger was the indication that a total
of 257.97 TB in 423,710 files had been found. Now,
finding 250 TB on a 1 TB drive seems like quite a
remarkable feat!
The partitions that had been located were listed in the
form: Partition 1 NTFS, Partition 2 NTFS, etc. Each
partition was nominally several tens of GB in size, and
contained thousands of files and folders. Not really
knowing where to start, the choice was made to look at
the contents of the first listed partition. In
particular, Jeff was interested in trying to recover some
WordPerfect files, so the initial investigation was
undertaken in the RAW Files/Word Perfect Document folder.
This proved
not to be particularly helpful. All of the files were
listed in the form file1.wpd, file2.wpd, etc. The
recovery software appeared to have grouped the WPD files
together but had been unable to recover the original file
names. Furthermore, attempting to open these files
revealed a further problem. Some files appeared to have
been recovered successfully, e.g. there were a number of
letters and the odd software manual that were easily
read. However, many files just contained pages of
“garbage” (ASCII) characters or could not be
opened at all.
Jeff had further specified that the documents he wished
to recover were associated with his university law
courses and all had filenames in the form LAW*.wpd. Power
Data Recovery provides a Find option so this was used to
search the recovered information for this wildcard
filename.
At this point, a bug (or a feature) was found in the
software. Each press of the Find option produced a
listing for one file. Firstly, the file
$Dir9316/LAWS5903W.wpd was identified. A second search
located the file $Dir9335/LawSociety.wpd. However,
subsequent Find commands just cycled between these two
files, and the process continued in a seemingly endless
loop.
However, the really bad news was that even though only
two “LAW” files were identified in this manner,
both of them contained unreadable ASCII characters. So,
there was no useful recovery using this method.
Our problem now is knowing whether the recovery software
isn’t doing its job for a hard disk, or if the
format used by the JBOD array is so weird and wonderful
that recovering individual files from just one disk is
really a non-starter.
I happened to have a spare hard drive available, one
which I had replaced in a laptop computer with a SSD.
Since there was nothing wrong with this disk, I thought
it might be useful as a test bed for a partition
“recovery”.
One of the partitions on the drive was an old version of
my dedicated data partition. For the test, I deleted this
partition using the Disk Management utility, did a Quick
Format of the partition, and then copied the files and
folders for my current data partition from my backup USB
drive to the test HDD. The data partition on the test HDD
now had exactly the same files and folders that were on
the backup USB. Finally, I deleted the data partition
once more from the test HDD.
Running Power
Data Recovery allowed me to conduct a full scan on the
now 8.01 GB, unallocated, partition on the test HDD. The
results showed that the recovery software had located
“7.77 GB in 10,502 files”. In particular, there
were two recovery folders – “#1 (NTFS) 8.01
GB” which listed 4.7 GB in 5870 files, and “#2
(ALL RAW Files”) which listed 3.07 GB in 4632 files.
I saved the recovered folders to the main hard drive of
the computer being used to run the recovery software.
The first of
these folders contained recognizable files and folders
from my data partition. However, there were also two
additional sub-folders – GB and RAW Files. GB had no
files that were meaningful to me; just two folders, one
with some empty files, and another with some sort of
metadata files. The RAW Files folder contained the
sub-folders that we have seen previously, e.g. Word
Perfect Document, etc. with file1.wpd, et seq. Since
these folders didn’t appear to be useful, I simply
deleted them, leaving the files and folders that I
recognized as coming from the deleted data partition.
The final stages in the recovery process were to use the
Disk Management utility to set up the unallocated
partition on the test HDD as a simple volume, assign a
drive letter, and to copy the recovered files and folders
to this newly-created partition. It was then a simple
matter to do a file and folder comparison between the
recovered disk partition on the test disk and the backup
USB drive to ensure that all of the files had been
recovered successfully.
So, the moral of this part of the story is that Power
Data Recovery will recover files completely from a
“lost” partition in some circumstances, but may
be considerably less successful under other conditions.
Either that, or I need to spend considerably more time
and effort to understand how the software works!
Final Thoughts
Power Data Recovery proved to be useful in a number of
instances, recovering lost files from various disk
storage media. However, users need to be aware that full
scans of large-capacity drives take considerable time,
even when using a computer with a fast CPU, tons of RAM,
and an SSD as the main drive. Furthermore, the recovery
software seems to hog the machine’s resources and
can dramatically slow the response for certain other
tasks that you may wish to run concurrently. This is
especially the case when trying to review the details of
the results, save recovered files, and access these files
in other programs in order to check their viability.
Finally, the scan results themselves are not terribly
intuitive. This may not be an issue if the recovered
files and folders are in the form that you expect, but
the information can be difficult to interpret in some
other cases. However, the successes that have been
demonstrated by a neophyte user suggest that this
software is deserving of a place in anyone’s
recovery toolbox. It provides a measure of insurance
against data loss, and may well be an exceptionally
useful tool for this purpose in the right circumstances.
Bottom Line:
Power Data Recovery (US $89.00)
MiniTool Solution Ltd.
Vancouver, British Columbia
https://www.powerdatarecovery.com/
Originally published: November, 2017
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