increasing number of computer manufacturers, Apple includes a built-in hardware
diagnostic test in their systems to help users or system administrators
diagnose hardware faults. Apple Hardware Test (previously, Apple Diagnostics) comes
in short and long variants, will mildy stress components such as an iMac or
MacBook’s processor, logic board controller, fan motor, RAM modules and of
course the hard disk. For the latter, you would hope that the test is fairly
accurate so that your (or your user’s data) is not put in jeopardy.
“4HDD/11/40000000: SATA (0,0)” mean?
When Apple Hardware
Test does detect a fault with your disk, it will display the rather cryptic
error code “4HDD/11/40000000: SATA (0,0)”. This basically means that the AHT has
discovered that your hard disk is failing.
How Accurate is Apple’s Hardware Test when testing a hard drive?
unfortunately, Drive Rescue has come across a substantial number of cases where
the Apple Hardware test (short and long versions) did not detect a fault even
when a hard disk was failing.
several reasons Apple’s in-built disk diagnostic utility cannot be relied upon:
Apple’s Hardware Test performs a random scan of the tracks of your hard disk. It does not scan your whole hard disk. The test could easily miss sectors of your disk which are failing.
Apple’s Hardware Test cannot detect firmware problems.
Apple’s Hardware Test will not always be successful in determining weak or unstable read/write heads. Often, during tests, random reads are short. In real-life, reads of contigious files can take much longer stressing the disk- heads much more.
Apple’s Hardware Test cannot detect electronic issues with your disk’s PCB.
Apple’s Hardware Test cannot detect whether you have a corrupt HFS+ or APFS partition table.
In summary, the in-built testing hard disk which Apple provides with their iMac, MacBook and Mac Mini systems is just rudimentary disk diagnostic tool. It should not be regarded as infallible litmus test of a hard disk’s health.
Drive Rescue Dublin offer a complete data retrieval service for Apple Mac computers in Dublin. We recover data from dead iMacs, MacBooks, MacBook Air and Mac Minis. http://www.datarecoverydublin.ie. Prompt and professional service.
We recently had a customer who, when attempting to boot their Lenovo Carbon X1 laptop running Windows 10 laptop, got the “Inaccessible Boot Device” error message.
We removed the MZ-HPV2560 SSD from the laptop’s motherboard. The connection interface of the hard disk was proprietary. Using a specialised Lenovo Carbon X1 PCIe to S-ATA adaptor, we connected the SSD to one of our data recovery systems. However, the Windows volume on the disk still did not mount.
The MZ-HPV2560 SSD is really a Lenovo rebadged version of the SM951. The disk uses a native Samsung SSD S4LN058A01 controller and uses 16nm MLC NAND. Surprisingly, this solid state disk does not use NVMe.
After some disk diagnostics, we discovered that some microcode modules used in the controller were corrupt. We put the disk into technological mode and using highly-specialised SSD data recovery equipment repaired the corrupted modules.
The client needed several hundred .ODT (OpenOffice Writer) and .ODS (OpenOffice Calc) files recovered as part of a research project. These were all put on a USB stick and reunited with their over-joyed creator.
If you need to recover data from a Lenovo laptop or a Samsung SM951 SSD disk, we can help you. Drive Rescue have been recovering data in in Dublin Ireland since 2007. Our clients are based throughout Ireland including Dublin, Cork, Limerick, Galway, Ennis, Kilkenny, Carlow, Waterford, Wexford and Dundalk www.datarecoverydublin.ie
recovered data from two S-ATA disks removed from a Dell XPS desktop.
The two Seagate Barracuda (ST31500341AS) disks were configured in RAID 0 mode. Instead
of using a hardware RAID controller such as PERC or Adaptec card, the host system
was using RAID BIOS. This type of RAID utilises the BIOS along with Intel
chipset software (installed on the operating system) to manage the RAID.
disk diagnostic tests revealed that disk # 0 was in rude health. However, disk
# 1 had defective read/write heads #2 and #3. The disk heads are a crucial
component of an electro-mechanical hard disk as they read the data from the
disk platters. When two or more heads fail, the only way to recover all the
data is to remove the head-disk assembly and replace it with a part of the
exact same specification. Near-matchs will not suffice. In this case, we
already had a donor HDA in stock.
up the faulty Seagate 1.5TB S-ATA disk in our clean-room and used a device
known as a “head-comb” to carefully remove the head disk assembly from the disk
chassis. The new head-disk assembly was delicately inserted and was then
secured using a Torx screwdriver. Just the right amount of torque pressure needs
to be applied – too much or too little can result in the head-disk assembly mis-aligning
with the platters. The disk then had to be slowly imaged (onto another disk)
which would be used in the next stage of the recovery process. It is always
preferable to work with disk images as opposed to the original disks to
maintain data integrity.
The RAID rebuild process
images of disk 0 and disk 1 attached to our RAID data recovery system, we
started the rebuild process. After determining the block order and block size
and other parameters, we inputted these into our RAID data recovery system. The
rebuild process started and 6.5 hours later and we had a complete and fully
mountable NTFS volume. Using random sampling, we checked the integrity of files.
Word, Excel, PDFs and Jpegs all opened up perfectly.
Notes on this case
Dell brought out their XPS range of desktops aimed fairly and squarely targeted at the consumer market. A substantial number of the mid-to-high-end models in this range (from around 2008 to 2014) came with RAID 0 (in a two-disk configuration) enabled by default. So, while some owners are (understandably) comforted by the fact that their system has two disks instead of a paltry one, not all realise these disks are joined at the hip using RAID 0. Dell really should have put a health warning sticker on these systems. “Dear User, You have two disks inside your system in RAID 0 configuration. This is for a larger storage volume and should not be considered a backup…”
helped a Dublin marketing company recover data from their Western Digital EX2
My Cloud Personal Storage drive. The NAS device was no longer recognised on
their network. Unfortunately, it stored marketing materials for several clients
stored on it which was not backed up elsewhere. File types which needed recovery
included .INDD files (InDesign), .PSD (PhotoShop), .HTML, .MOV and .JPEG files.
They really needed these files salvaged and fast!
While WD My
Cloud storage devices are popular and relatively reliable, occasionally things
can go wrong.
Why your WD My Cloud NAS is no longer
The EXT4 file system which your My Cloud
device is using has gone corrupt.
The RAID array has degraded. Depending
on your model of My Cloud, some of these devices can be put in RAID
configurations of 0,1,5,10 or in JBOD mode. When the RAID array fails or degrades
the My Cloud device will no longer be recognised by your network or on client
One or more of your disks has head
disk assembly issues.
One or more of the disks has firmware
issues which is causing your device to be unrecognised.
One or more of the disks have extensive
bad sector issues.
Your My Cloud device may have a
damaged PCB (controller board) due to a power surge.
particular case, the users tried to access their My Cloud data but kept on
receiving the error message:
“We’ve detected that you may not be able to recognize the device on your network”.
The 6TB disk
(WD60EFRX) which we removed from their My Cloud EX2 device had firmware issues
and extensive bad sectors. We first resolved the firmware issues (corrupt translator)
and then proceeded to resolve the bad sector issues. We succeeded in an 98%
recovery rate. The workflow of our
delighted client was not interrupted and their reputation for delivering
quality work, on-time was kept intact.
Need to retrieve data from a My Cloud drive? Drive Rescue Data Recovery Dublin (Ireland) offer a complete data recovery for all WD My Cloud NAS devices, including the DL4100, DL2100, EX4, EX2 Ultra, Mirror Gen2, WD My Cloud Mirror and PR2100. Phone us on 1890 571 571 or visit www.datarecoverydublin.ie or www.nasrecovery.ie
Recently, Drive Rescue were in Nuremberg, Germany, attending EmbeddedWorld 2019. While this event primarily caters for electronic systems, edge computing, IoT and energy efficiency, it also hosts a number of storage device manufacturers.
NAND, NAND, NAND – it’s everywhere
In fact, one could hardly walk 20 metres in the exhibition halls without encountering NAND memory in some form or another, from either systems integrators or the manufacturers themselves. The latter were displaying NAND in more visible forms, such as in USB devices and SSDs.
From Industrial machines to torpedoes
The affable team from Transcend explained how their NAND-based memory products are widely used in everything from industrial machinery, slot machines, robotics to torpedoes. These are areas not normally associated with “boring” storage. Transcend are suppliers to Kuka, one of the world’s largest robotics manufacturers, whose robots are used in everything from car manufacture to nuclear decommissioning.
High-quality NAND is essential in applications such as these – for example, a robot will constantly read and write to NAND memory. (Transcend recommends using its “SuperMLC” NAND, which is MLC memory designed to emulate the reliability of SLC, for uses such as these.) Likewise, durable NAND is essential for medical devices that use logging capabilities, such as heart rate monitors. I asked the Transcend team what sets them apart from the competition and the emphatic answer was “quality control”.
What butchers and NAND suppliers have in common…
Transcend source NAND wafers from either Samsung or SanDisk. A wafer is like a large sheet of NAND. The best quality NAND chips (or prime cuts) are in the centre with the lower-quality NAND chips (offal) residing at the fringes. Transcend only use prime cuts of NAND for their memory products. (Low-quality NAND probably ends up in generic USB sticks sold on eBay or in SD cards sold in street markets.) Once cut. the company use an extensive four-stage testing process to weed out any defective NAND. This is important if your NAND is being used for torpedo guidance systems. However, even with stringent quality control processes, people still lose data. The Transcend team explained how human error is the biggest cause of failure for their SD cards. For example, they manufacture consumer-level dash cams. For those motorists unlucky enough to be involved in an accident, their first instinct is to seize evidence of the event. So, with their dash cam still running, they pull the card out and, ironically, end up corrupting the very information they want to preserve. Murphy’s Law in extremis.
And talking of data preservation on NAND, the Taiwanese SSD manufacturer ACPI sees sudden power loss as a major issue for industrial PC, enterprise servers and professional grade photo systems. This can still occur even with a UPS deployed. For this reason, ACPI has brought out its “Power Shield” technology for its SSDs. This protects a data write even during total power loss. Capacitors store a residual voltage which enables any tunnelling electrons in the floating gate to reach their destination safely.
Sony enters the consumer and industrial SSD market
Sony was a surprise exhibitor at EmebeddedWorld 2019. While not normally associated with SSDs, it has been dabbling in solid-state storage for quite a while. (Primarily sourcing its NAND from Toshiba and controllers from Phison.) Sony’s USB memory sticks and SD cards have been on the market in Ireland for a number of years. Many readers of this blog might be familiar with its distinctive “Memory Stick Duo” cards that were first introduced on the market circa 1998, in the nascent days of digital photography. Those involved in professional TV and film production who use Sony kit will probably be familiar with its SxS cards for professional grade camera equipment. These cards, now called SxS Pro+, are still being produced by Sony and offer capacities of up to 256GB, offering write speeds of up to 400MB/s. For commercial/industrial customers, Sony now offers a range of M.2 SSDs optimised for heavy-duty use. It will shortly be introducing external SSDs for the consumer market with USB-C interface and capacities of up to 960GB.
Toshiba – the inventors of NAND
technology was invented, semiconductor design had to rely on EPROM and EEPROM.
But both of these technologies were relatively slow and could only store the
most basic of information. That was until 1984, when Fujio Masuoka of Toshiba
came along and wrote a research paper on a revolutionary type of memory design
called NAND. Toshiba’s first NAND went to market in 1989 and the rest is
history. NAND has been getting denser, faster and more capacious with every new
3D NAND Fever
The current iteration of NAND that Toshiba is marketing is its 64-layer 3D BICS NAND. One of the Toshiba team described how the market is now in a state of “3D fever, as everyone wants a piece of the 3D NAND action. Toshiba is currently using 15nm 64-layer 3D TLC “Bics” NAND in the majority of its SSD devices. According to Toshiba, its “charge-trap” technology is more reliable than “floating-gate” (which is actually a technology from the 1970s). The latter transistor design holds electrons like “water in a glass”, whereas “charge-trap” technology is “more like a sponge”. The electrons are less likely to leak and, therefore, more likely to maintain the integrity of your data. The next iteration that Toshiba expects to commercialise is its 96-layer 4-Bit QLC NAND later on this year.
Although Toshiba is known for inventing NAND, they still manufacture mechanical hard disk drives. (In fact, Toshiba’s hard disk and SSD operations have now been spun into two separate divisions). With the current trend for Big Data analytics and virtualised storage systems, Toshiba is adapting its product lines. For example, its “AL” series of disks are designed for use in Tier 1 enterprise servers. These disks use a SAS interface and have capacities of up 2.4TB with a MTTF of 2 million hours. Toshiba’s “MG” series caters for enterprise storage arrays. The MG07 and MG08 can hold up to 14TB and 16TB of data respectively. These whopping storage capacities are achieved with the assistance of helium, which is injected into the main chamber of the drive. This is then laser-sealed. Helium enables smoother writes that are closer to the platters and reduces power consumption. Moreover, these disks contain 9 platters instead of the competition’s 8. (We’re glad to see that Toshiba is not skimping on platters. As a data recovery company, we know what can happen when manufacturers try to economise on them… Seagate’s calamitous “DM” series of 3.5” disks being a prime example). This series of disks also use MAMR (Microwave Assisted Magnetic Recording) whereby a Spin Torque Oscillator of frequencies between 300GHz and 300MHz saturates the bit areas of the platter with a concentrated microwave field, which enables more reliable writes in high-density disks.
this technology means that we might be seeing 28TB or higher capacity HDDs in
the not too distant future. It will be interesting to see what approach Seagate
will adopt with its disk-heads as its HAMR technology has come in for sustained
criticism for stressing disk platters (not to mention the users…) For non-data
centre disks, Toshiba also makes disks for the SME and personal market. Its N300
disks, designed for NAS, come in sizes of 4-14TB, designed for 24/7 usage.
Toshiba also makes standard mechanical disks, such as the P300 (3.5” S-ATA) and
L200 (2.5” S-ATA).
Maybe it’s all the crime thrillers that people are watching on Netflix or the Dublin gangland documentaries being shown on Virgin Media One, but there’s been an explosive growth in home surveillance systems in Ireland recently. Similar trends are occurring worldwide and hard disk manufacturers are responding to this demand. WD already has its “Purple” disks, Seagate its “Skyhawk” line-up and Toshiba its “S300” surveillance hard disks. This disk (picture above) comes in capacities of 5TB to 10TB and is designed for 24/7 operation. It’s a “write-centric” disk, meaning that its disk-heads and firmware are optimised for 90% writing and 10% reading.
According to the NAND and SSD manufacturer Micron, this growth can be partially explained by the precipitous drop in prices for 2K and 4K image sensors (a key component of camera manufacture). But growth in surveillance is also being boosted by the next-generation SOC (system on chip) security systems, which use deep learning and AI (Artificial Intelligence). Where once security systems or facial recognition technologies would just capture and store, now they can capture, store and analyse. This was presciently portrayed in the James Bond movie TheLiving Daylights (1987), where the baddie Max Zorin used facial recognition technology in his office to identify James Bond in a matter of seconds. Surveillance systems now need to perform analysis in real-time without the latency incurred by communicating back to a centralised cloud-based server. Imagine an AI-powered surveillance system in an airport that detects a passenger at the boarding gates who is on a “no-fly” list. Even with a relatively fast link to “the cloud”, image retrieval and analysis might still prove too slow. If that same surveillance system used edge-based SSD storage, the storing, analysis and processing of images of the system would be vastly accelerated.
In use cases
such as these, NAND is the big enabler. A body or dash camera using a 2.5”
spinning disk would probably not last too long in the field. While NAND has
been on the market for a relatively long time now and its evolution to layered
versions or “3D” means we now have higher capacity reliable storage in a very
small form factor. Micron was exhibiting its “C200” microSD card which was
released at the Mobile World Congress in Barcelona just a few days previously.
This Lilliputian card uses 96-layer 1TB QLC 3D NAND with eight 128GB dies. It
has write-speeds of 100MBps and read-speeds of 95MBps. If Micron can scale its NAND
to 256-layers, I’ve no doubt that we’ll be seeing 2TB and 4TB versions of this
might be thinking, does the average consumer really need 1TB of storage in
their camera or phone? Well, a substantial number of consumers now expect to be
able to shoot footage on their phones or action cams in 4K HDR quality. (To
give this question some perspective, only twenty years ago phone manufacturers
were asking themselves, do consumers really need cameras on their phones at all?)
While a card like the “C200” might be fine for a consumer-level smartphone or action cam, it might not be the ideal solution for other use cases. For instance, the primary storage in edge-based surveillance systems is often in the camera itself. (Having the storage here eliminates the network congestion that is generated by IP-based cameras and frame loss due to network disruption). The storage medium in such a camera means it is going to be exposed to constant writes. This is something that a QLC-based NAND card would not be able to do! For this, reason Micron has brought out industrial-quality TLC-based SD cards using 3D NAND (such as the MTSD256AHC6MS-1WT). Its high-capacity models can store footage for up to 30 days and come equipped with a card-lock to prevent tampering. Micron also offers a health management API to proactively warn system administrators of potential SD card failure.
The future of computing is edgy…
only in surveillance that edge-based storage is playing out. IDC Research
estimates that in the next 3 years, 45% of IoT generated data will be stored,
processed and analysed at the edge of the network. And this is something that NAND
and SSD manufacturers are extremely interested in. Edge Computing offers faster
response times, more reliable operations in areas of poor internet connectivity
and better data security. Most Android smartphone users that use Google Maps’ “offline
maps” feature know the benefits of having local storage. It’s often
significantly quicker than the device having to communicate with the cloud. It
is being touted that autonomous cars are basically going to be “servers on
wheels”. It is inevitable that these cars will traverse areas where internet
connectivity is poor. Here SSDs and NAND will play a pivotal role in not only mapping,
but also enabling the execution of the car’s key software functions.
pervasiveness of high-speed high-capacity is going to make our lives easier. Ever
tried to buy a train ticket from a self-service kiosk on a busy rail network at
peak time? You have probably noticed that the loading of the menus and
timetable information is laboriously slow. It’s more than likely that the
ticketing machine, along with hundreds of others, was simultaneously communicating
with a central server and the network was congested. Taking an “edge computing”
approach to this problem, key information, such as timetable information, is
stored locally on the ticket machine (just like Google “offline maps”) while
data, such as real-time updates and seat availability, are transmitted in the
form of compact, computed findings rather than raw information. Or let’s take the
example of a wind farm off the west coast of Ireland. While it’s probably still
within connectivity reach of 3G or 4G networks, constant communication might be
more problematic. Storage on the “edge” can mean there is no data loss or
operational failure in the event of limited connectivity. This is not to say that
the Cloud is going to become redundant, but it will take a more passive role in
our lives – partly enabled by advances made in NAND memory technology. Thank
you, Mr Masuoka!
Drive Rescue Data Recovery is based in Dublin, Ireland. We offer a complete data recovery service for SSDs such as those from Toshiba, Samsung, Micron (such as 1100 M.2, M500 and M550) and SanDisk. We also recovery from Toshiba portable hard disks such as the Toshiba Canvio (DTB320, DTH 305, DTH310 and DTH320) and recover from disks such as inaccesible WD My Passport Ultra portable disks with blinking lights. Find out more at: www.datarecoverydublin.ie
recently helping a customer solve an issue with an inaccessible Maxtor M3
(Model HX-M201TCB/GMR) disk which was showing a flashing blue light when
connected to a PC. The disk made a healthy spinning noise but was not appearing
in Windows explorer. Much to the dismay of the user, a university lecturer,
over 3 years worth of PowerPoint presentations were not appearing.
Maxtor enclosure, we found a Seagate disk which was no surprise as the Maxtor brand
is owned by Seagate. The first problem we discovered with the disk was an
overflowing G-List. This an area of the firmware designated for recording bad
sectors. Using specialised data recovery equipment which can manipulate the
disk at firmware level, we cleared this list. Next problem was the 19,872 bad
sectors. We programmed our recovery system to read the disk allowing for a read-delays
of up to 900 milliseconds. We also programmed our system to read the disk using
a block size of just 60 sectors per read. This would allow us to maximise the
chances of the best possible recovery for the client.
Now with an
image of disk, we programmed our system to image the disk in reverse mode. This
covers areas which the forward disk-read passes would have ignored. On
completion, the bad sector count had been whittled down to just 944.
17GB of PowerPoint lectures (.PPTX files) were recovered and reunited with the delighted user.
Need to recover files from a Maxtor M3 external hard disk in Ireland? Drive Rescue have been recovering data since 2007 and can help you. Visit www.datarecoverydublin.ie for more information. Or call us on 1890 571 571.
Last week Drive Rescue recovered data from this hard disk which
was removed from a Dell laptop. The disk had a seized spindle (see previous
blog post for another Seagate disk with a seized spindle, the recovery process
The user’s IT support team from a company in Carrick-on-Shannon,
Co. Leitrim came to us for assistance because the Seagate disk was making a buzzing
noise when trying to initialise.
Even after recovery, the volume was still inaccessible because
the disk was encrypted with TrueCrypt (AES 256 in XTS mode). However, after the user had emailed us the encryption
key, we decrypted the disk and were able to mount the NTFS formatted volume. All of their Solid Edge (.IGS and .IGES)
design files were successfully recovered.
recover data from a Seagate Laptop Thin HDD? Drive Rescue are based in Dublin, Ireland
and offer a complete data recovery service for Seagate laptop hard disks. www.datarecoverydublin.ie
The ST1000LM035 is a mechanical 1TB 5400RPM S-ATA mechanical disk from Seagate introduced in 2016. It’s capacity and thin 7mm form factor has proven extremely popular with laptop manufacturers such as Dell, Acer, Asus and HP. The aforementioned companies all desiring to make their computing devices as slim as possible. In turn, since around 2010-2011, hard disk manufacturers have responded by introducing thin form factors (7mm) for their 2.5” S-ATA disks. (The standard 2.5” S-ATA being 9.5mm). However, from our experience spindle motors used in “thin” disks have a high propensity to fail than motors used in standard 9.5mm disks.
Spindle failures such as seizures was an extremely common problem
generation hard disks, spindle failures such as seizures was an extremely
common problem. Most of these disks using
conventional ball bearings had a tendency to experience a phenomenon known as “non-repetitive
run out vibration”. This occurred due to nano-metre inconsistencies found on
the bearing balls causing read/write interference. In worst case scenarios the
spindle would seize altogether making the disk inoperational.
From conventional ball-bearings to fluid-dynamic bearings
Then around 2002-2003, spindle motor manufacturers began using fluid-dynamic bearings. This was a paradigm shift for mechanical hard disk design. Fluid dynamic bearings use a fluid such as oil between the bearings and the shaft. When the shaft rotates the pressure generated by the fluid helps the bearings move more smoothly. While this led to greater disk reliability, it also made hard disks run more quietly and saved computer users the irritation of having to listen to metallic scraping noises.
But the pull of technological innovation never sleeps. Just as spindle motors used in 9.5mm disks were going from “reliable” to “extremely reliable”. Spindle motor manufacturers had to go back to drawing board to design models suitable for 7mm disk form factors. This would mean a complete redesign or a compromised design. Spindle motor size can only be 70-75% the thickness of the disk. Most spindle manufacturers seem to have taken their motor designs for 9.5mm disks and “cut them down to size” to fit the smaller form factor disks. From a reliability standpoint, the “thinner and lighter” trend pervasive in hardware at the moment is a classic example of two steps forward one step back.
Two Steps Forward – One Step Back
slimmed down design, the bearings have less room to build a suitable magnetic
force needed for a 5400 RPM platter. Maybe this is because the motors used in this
form factor are not as reliable as those deployed in 9.5mm disks. (Other 2.5”
7mm disk models such Western Digital’s WD10SPCX and Seagate’s Momentus Thin also
exhibit spindle motor problems).
Recovering data from a beeping hard disk
particular case, the ST1000LM035 disk which was removed from a Dell laptop was
beeping. We transplanted the disk platters containing their client’s data using
a customised unwinder tool designed specifically for use with Seagate 2.5” thin
disks. We removed the platters and transplanted them into an exact-match
Seagate ST1000LM035 donor disk. Platter removal is an extremely intricate job.
For a successful transplant, a number of criteria must be met. These include:
alignment between the platter unwinder tool and notches of the platter ring. Otherwise
torque forces might incur further damage.
must apply a clockwise force. Remember, most hard disks spin in an anti-clockwise
platter securing ring must be carefully removed with a tweezers. These must be free
from any residual magnetic forces and must not touch the platter surface.
transplanted platter must align perfectly with the notches on the donor disk. This
can be achieved by rotating the platter-tool until you feel a slight click.
the hard disk ramp has returned to its original position the disk lid can be
In recovering this disk this methodology was followed. But upon disk initalisation the volume could still not be seen by our host system. Such surprises are to be expected in data recovery. One common reason for such an occurrence is the new spindle not being “tuned” to the new disk. This can be remedied by using a firmware emulator. We did this and restarted the disk. This time a volume appeared with the client’s Word, Excel, Photos, PDFs and .RVT (Revit) files now being accessible. We performed an integrity check on these and they were perfect. These files were extracted onto a USB portable disk and delivered to a very happy customer.
Drive Rescue is based in Dublin, Ireland. We hope you have found this post useful and interesting. We have also successfully retrieved data from the 2TB model (ST2000LM007) of the disk mentioned in this case study. Other “thin” disks which we recover data from include the Seagate Momentus Thin, WD Blue models WD10SPCX, WD10SPZX and HGST Z5K500, 5K1000.
were recently at the Capuchin Day Centre to present this extremely worthwhile
charity with a donation. We know this
does not solve the homeless problem in Dublin but some help is better than no help.
A Longford-based customer recently sent a 1TB Seagate Backup Plus disk for data recovery. When connected to a Windows PC, the following error message was displaying:
D:\ is not accessible
Data error (cyclic redundancy check)
Cyclic Redundancy Check is a mathematical equation used to ensure the integrity of data. It works by multiplying the number of bits in the data packet by a pre-determined number prior to data transmission and retains the answer. Once the data is received, it executes the same equation again. If the two answers match, your computer processor knows the data is intact. CRC checking is commonly used in TCP/IP networking but is also in disk-to-disk communication such as when an external hard disk or USB memory device is connected to a computer.
Fix Cyclical Redundancy Check errors
Typically, the Cyclic Redundancy Check error message tells us there is a problem with a storage device. In a small minority of cases, the issue can be resolved by running the Checkdisk (Chkdsk) command on the disk within Windows. However, in the vast majority of cases the Cyclic Redundancy Check error message is indicative of a more serious problem with a disk.
In this particular case the client’s Seagate Backup Plus disk had over 20,000 uncorrectiable bad sectors. We used our specialised data recovery equipment to “read around” these sectors and then performed a “read retry” operation on them. Our equipment does this at a very low level, meaning we can access data which would be otherwise unreadable to operating systems such as Windows, OS X or Linux.
We were successful in recovering all the file types needed by the client. These included .docx, .xlsx and .mdf (Microsoft Access) files. Case was closed with one extremely satisfied customer!
Drive Rescue Data Recovery Dublin offer a complete data recovery service for external hard disk drives such as Seagate Backup Plus, WD My Passport, MyPassport Ultra, Freecom Toughdrive, Maxtor M3, Toshiba Canvio, Transcend and Verbatim. To find out more visit: www.datarecoverydublin.ie