• “100% successful. Well done”

    Ross Lindsay Cumbernauld

  • “A company that clearly knows exactly what it is doing, delivers exactly what it promises and does so without any fuss, just excellent service.”

    Howard Wilson Bristol

  • “Over the moon with the service, and the fact that I have all my data back is an absolute lifesaver.”

    John McNiff Pontefract

  • “You expect efficiency as standard and once you've got it, you realise that friendliness is extremely important too. Tierra does really well in both areas.”

    Daniel Batista Millares London

  • “Definitely worthwhile using your services to get back what everyone else was telling me was lost! Those photos and accounts are priceless.”

    Paul Edwards Liverpool

  • "I found Tierra to be clear, concise, straight forward, friendly, extremely professional, competent and highly knowledgeable."

    Callum Donez North East Lincolnshire

  • "Tierra salvaged my backup, with persistence that I can't have imagined."

    Gordon Dodds Cornwall

  • "Tierra stepped in quickly, efficiently and professionally restored all my lost data. Outstanding quick service."

    Jonathan Crombie Crombies of Edinburgh

  • "The level of customer service I experienced from your company was very impressive."

    Diane J Earle London

  • "This company truly understands the concept of time-critical recovery."

    Professor Ben Kneller University of Aberdeen

  • "Thank you for your professionalism, speed and quality of work."

    Anna Mavrogianni London

  • "No hesitation in recommending your company to anyone."

    Phil Codd Doncaster

  • “Thank you again for doing what the first computer repair shop I visited told me was basically not possible.”

    Kenny McLeish Carluke

  • “Tierra rocks!”

    Stephan Ringer London

An Example of the Procedures Involved in Hard Disk Recovery from a Drive Which Has Suffered Electrical Damage

We received a call from an IT company for whom we routinely carry out hard disk recovery work one day. They had a very worried client who had some irreplaceable files on a laptop hard drive. In this case a Toshiba model MK2546GSX, which is a 250GB S-ATA drive. Both the client and the IT company had carried out some initial analysis and the reported conclusion was that the “motor had burned out”. In other words on application of power there was no attempt by the drive to spin-up, in fact no signs of life at all. It was time for some professional hard disk recovery work.

The first step towards Hard Disk Recovery, The Initial Analysis:

More often than not when a hard drive has been subjected to the incorrect voltage the resulting damage to the printed circuit board (PCB) will leave the hard drive presenting a short-circuit to the computer’s power supply. A short-circuit can severely damage a power supply and consequently it is always wise to test for such damage on any suspect hard drive. Sure enough initial testing demonstrated that the PCB on this drive had developed a short. This usually happens in response to too high a voltage supply. This in turn is usually because the hard drive is accidentally connected to the wrong supply voltage by the user; it may be due to a supply spike from a less than reliable power supply unit in the computer or simply down to bad luck with your local mains supply. However the electrical damage has been caused, a successful hard disk recovery will depend upon an accurate diagnosis of the resulting damage.

Having established that the problems were electrical, the next step was to investigate and attempt to repair the PCB itself in isolation. The PCB was duly removed and investigation began. It soon became apparent that there had been multiple component failures (although, as is often the case, there was no outward physical sign of damage). Where electrical damage is relatively slight then it is practical to replace and / or work around failed components in order temporarily to get the PCB working again, at least for long enough to get access to the data. However in instances such as this case where the damage is simply too extensive for this to be realistic it is necessary to source a closely matching donor hard drive and use its PCB as a replacement. Unfortunately a simple swap will almost certainly not regain access to the drive data. The reason for this is that the PCB holds a chip which in turn holds some configuration information which is specific to this individual drive. This information is part of the hard drive’s firmware. Without access to this firmware information the drive may well spin-up but it is very unlikely that there will be access to the user data. For more information about swapping PCBs have a look at our article here.

In this case there was a further complication. Electrical damage will sometimes extend beyond the PCB. Given the extent of the damage evident here it was therefore no great surprise to discover on further testing that the pre-amplifier had also been fried. The pre-amplifier is a built-in part of the read / write head assembly (for more information on basic hard drive anatomy try our article). This would therefore necessitate the replacement of the entire read/write head arm assembly with equivalent parts from a closely matching donor drive. Such extra obstacles to hard disk recovery are unfortunately very common where a drive has been subjected to electrical damage.

The Second Step Towards Hard Disk Recovery, Getting the Drive Operational Again:

The donor drive was duly obtained and the read / write head assembly was removed and replaced with the donor parts. The donor PCB was removed and the chip storing the firmware removed. The equivalent chip from the original defect drive PCB was then removed and installed on the donor PCB. The drive was then re-assembled and powered-up.

Swapping the firmeare EPROM is an essential part of this hard disk recovery

The chip holding the unique firmware information (red arrow) is essential to the successful hard disk recovery

 

The Third Step Towards Hard Disk Recovery, Cloning the Defective Drive:

As soon as the drive had initialised, cloning to a fresh, healthy drive began. This is a critical step in data recovery and because it is time consuming and resource-intensive, one that is often omitted by companies working at the budget end of data recovery. It essential because there is simply no way of knowing how long a drive that has suffered damage will last, the data analysis and extraction work which will follow is intensive even for a fully healthy drive and so the chances of a severely damaged drive failing while these procedures are  under way is relatively high. Of course if the original defect hard drive fails under these circumstances then the recovery efforts will have come to a (premature) end. Once a healthy clone has been produced then the subsequent recovery work can be carried out on that clone without jeopardising the data.

The Fourth Step Towards Hard Disk Recovery, Data Identification and Extraction:

Once the clone had been obtained the original client-supplied drive could finally be abandoned. All subsequent work would now be carried out on a fully healthy clone.

The drive was scanned using our own in-house software and the user data extracted. In this case there were no logical complications the file system was NTFS (used with almost all Windows operating systems). It is often the case when the original hard drive has cloned only partially that some of the user data is no longer referenced through the still-readable parts of the file table. Where this has happened then deeper scanning is required to locate the remaining user data.

The Final Step to Complete the Hard Disk Recovery, Verification of the Recovered Files:

The final step is another vital one which is often side-stepped at the budget end of the data recovery market, the task of verifying that the files recovered will open and are not corrupted. The only way to know whether or not a file has been recovered intact is to open it. For more information about why a file list is not a reliable guide to what data has been recovered read this. In a nutshell there is no software which can reliably verify that files will open. Therefore it is incumbent upon any data recovery company to open the files in question using the appropriate applications to confirm that they have been recovered intact. Often, of course, a recovery will consist of tens or hundreds of thousands of files, in these situations extensive sampling must be carried out combined with an offer to the end user to check any individually critical files.

Thorough sampling in this case confirmed our faith in the recovery. The end-user did indeed have some specific documents that were critical and after verifying that these were intact we were in a position successfully to conclude the hard disk recovery.

 

While we are always grateful for the business, data recovery is obviously something that you want to avoid, so what is the best way limit your exposure to the risk of losing your data to hardware failure?

Option 1: Buy the World’s Most Reliable Make of Hard Drive?

At Tierra we are often asked for our recommendation for the best hard drive to buy. The reality is that after almost a decade in the business of data recovery we have learned that there is very little to choose between the various manufacturers. We have seen that the proportion of individual makes and models of hard drive that arrive in our labs for data recovery work broadly reflects the proportion in which they are sold. Each manufacturer’s drives tend to have their own unique vulnerabilities and foibles but ultimately the failure rate across the board is largely uniform.

Let’s make the imaginary assumption that there was one particular make and model of hard drive which was demonstrably more reliable than all others, it still would not and could not guarantee that your data would be safe. Nothing is 100% reliable and you have to tailor your behaviour to account for this fact. This will apply regardless of whether the hard drive you have bought is 99.99% reliable or a complete data-trap.

We are asked which drives we buy for our own use, the answer is – the cheapest. There is only one fact regarding hard drive reliability that anyone need take heed of and it is that every hard drive will fail eventually, we just aren’t given the foresight to know whether it will happen today or in 5 years time. Given this simple fact then the best advice is to buy the cheapest hard drive, but buy two and make a point of copying the contents from the first to the second on a regular basis.

Option 2: Make Regular Manual Back-ups of Your Data?

Now we are getting realistic, protecting your data requires a bit of active effort (although as we will see there is helpful hardware out there to assist).

The fundamental question is – what constitutes an adequate back-up? There are differing opinions on this of course but most would agree the following points:

-Critical data must be in at least 2 physically separate locations.  Ideally these two locations would be in addition to the working copy. Note that two hard drives within the same computer does not constitute different locations. A single voltage spike on the computer’s power supply could simultaneously destroy both hard drives.

Avoiding data recovery means having your data in different locations

Two hard drives within the same computer is not a reliable backup

-Ideally a critical file should be held on your computer’s hard drive (the “working copy”) an external hard drive (perhaps for a weekly back-up) and a memory stick (to hold a daily back-up of your current work). The risk of omitting one of these back-up destinations is that you may lose your vital data during the process of backing up itself. It is a surprisingly common story in any data recovery lab, the client was copying data from their computer to an external hard drive, something went wrong and now the data does not appear to be present at either location. With a three-point back-up routine you can at least minimise your data losses should this occur.

Many external hard drives are supplied with synchronising software as an option. The idea of this software is that the external hard drive will automatically back-up all files in a nominated location or locations on your computer, typically it will first check each file to see if there have been any changes made since the last backup, often only those that have been updated will be copied across. Newer Mac operating systems have this type of software built in (it is called Time Machine). There is no doubt that such software offers a way of reducing the amount of time and effort required to back-up your data. There are however some important caveats:

-We often see occasions where data recovery proved necessary because of a mix-up over source and destination locations when running the synchronising software, often the user has accidentally swapped these and ended up overwriting newer versions of the files with older ones.

-Most of these synchronising software programs conduct what is called incremental back-ups, in other words only partial back-ups are conducted (usually just files that have changed since the previous back-up) this can make restoring your data from the archive a baffling ordeal.

The up-shot of this is that if you are going to use synchronising software to back-up your critical files then it is essential to check from time to time that it has done the job correctly and has indeed backed-up your data. If you do nothing else at least confirm once that you can restore all of the data from your synchronised back-up. It is far better to familiarise yourself with this process when your data is still safe on your computer than trying to do it for the first time with the added stress of potentially losing all of your data genuinely hanging over you.

A word on external hard drives.  These are available in two formats, the smaller (2.5” size) externals which are powered from the computer USB port, therefore requiring no separate power supply and the larger (3.5” size) which do require a separate power supply. People are understandably much more likely to buy the small portable variety and there is no question that this is the way the market is moving, however we have seen considerable empirical evidence to suggest that these have a tendency to require data recovery more often than their larger cousins.  The jury is still out on precisely why this might be, there is some suggestion that that older style USB ports (pre-USB 3) may not supply sufficient power to the drives at all times or that the problems are caused by users failing to follow the appropriate USB disconnect procedure before removing an external from a computer. In either case it makes sense to stick to the following when using the  smaller 2.5” externals:

1. Always use a “Y” USB cable (unless it’s a USB 3 port). This is a cable which simultaneously plugs into 2 USB ports on your computer, this in turn increases the amount of power that can be delivered to the external hard drive. Most external hard drives do not supply this as standard so you will probably have to buy it separately.

Get a USB 'Y' cable, it will reduce the likelihood that you will need data recovery

A USB ‘Y’ cable for your 2.5″ external hard drive is a wise investment

2.  Never simply unplug an external hard drive from a USB port, always click on the USB disconnect icon and wait until the “safe to disconnect..” message appears, this gives the drive long enough to shut-down in an orderly manner.

 

Always follow the correct procedure when disconnecting your external hard drive

 Option 3: Use a RAID to Store Your Data?

For a full introduction to RAID have a look at our Dummies Guide here. In essence a RAID is typically an external data storage device which houses multiple physical hard drives configured to form a single storage volume. Different types of RAID perform different functions and are assigned different numbers. If avoiding the need for data recovery is your aim though then there are two RAID types that you should consider: RAID 1 and RAID 5.

RAID 1 (also referred to as a mirror) is typically composed of two physical drives. Every file is simply stored twice, once on each hard drive in the RAID array. This of course can slow access down a little but means that if one of the hard drives dies then you can still get your data back from the second. A typical example is this from Western Digital which holds 2 hard drives, the user can opt to configure them as RAID 1.

RAID 5 is composed of a minimum of 3 physical hard drives and offers increased speed of access to the data stored (when compared to accessing the same data stored on a single hard drive). More importantly it also offers significant redundancy. If any one of the hard drives within the RAID array fails then all of the stored data is still accessible. Only if a second drive fails before the first failure is rectified will data recovery become required. A RAID 5 can do this because in addition to storing the data itself the RAID 5 will also store additional information derived from the user data which allows the data on the lost drive to be deduced, this extra information is called “parity”. This of course means some of the storage space is not available for user data because it is needed for this parity data.

A couple of the more commonly encountered commercial RAID data stores are the Buffalo Terastation such as described here or the Lacie Quadras shown here but there are many others available.

RAIDs are undoubtedly the best way to protect against the need for data recovery, they require a minimum of effort from the user and yet offer significant redundancy, if you have the budget then they should be part of your data protection approach.

They are not however a complete guarantee, we regularly see failed RAID units in for data recovery and in our experience there are a few key points to bear in mind when using RAIDs (there is a detailed article on why RAIDs fail on this page), but in summary:

  1. Keep your RAID in a physical location where it can be seen (if one drive fails you may not be aware of it if you can’t see it).
  2. If one of the drives fails, don’t be tempted (or persuaded) to put off taking the necessary remedial action. The users will still have full access to their data and there may be a temptation to leave it for a while, don’t do it. If a second drive fails then you will need to seek out professional RAID data recovery.

 Option 4: Use the Cloud to Store Your Files?

This is now a widely available option. Why not keep a backup of your data on a remote server somewhere out in the world? There are some extremely notable advantages:

  1. Your files will be accessible from anywhere that you can gain an internet connection.
  2. It is an especially effective way of storing files that are required and shared by multiple users.
  3. It is incredibly cheap, in fact if you keep within certain capacity limits it can be free.

What are the downsides?

  1. Not everybody is happy with their data being located on an unknown server with the potential worry of what happens if the company operating it goes bust.
  2. Upload speeds tend to be much slower than download speeds and therefore you may be surprised just how long it will take to upload your files.
  3. Some people voice security worries over data stored on the web, however it is hard to argue that you are any more exposed to a hacker if your data is stored in the cloud than would be the case on your own PC with its internet connection.

Some providers of this type of online storage facility are Just Cloud, Zipcloud and Livedrive. Note that these are intended as examples only. We have never used any of these services and therefore are not in a position to endorse any specific cloud storage company.

Like all of the other options for keeping a reliable back-up, using cloud storage is an excellent option but should not be used as the sole answer.

Avoiding Data Recovery Can be as Simple as Spreading Your Files Around

Why not email your most critical files to yourself at another location. Or similarly give friends and family copies of your most cherished photographs, sharing can also perform exactly the same function as backing-up. The same could also be said about Facebook and similar enterprises but recent debates about precisely who owns such online content may have deterred many people from using this as a back-up mechanism.

A combination of these approaches is the answer, which work best for you will depend upon your personal circumstances and personality but adopt at least two of these back-up alternatives and it is very unlikely you will ever need professional data recovery in the future.

What You Need to Know Before Approaching RAID Recovery Services

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Clicking Hard Disk Recovery, A Case Study

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What is Involved in a RAID 5 Recovery?

RAID 5 is the most commonly encountered RAID configuration in commercial applications, there are good reasons for this, offering as it does an excellent balance between optimising the access speed to the data stored and protecting against data loss through hardware failure, however this doesn’t eliminate the very occasional need for RAID 5 recovery. For [...]

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RAID 0 Recovery, Why is it Needed so Often?

One of the more common requests that we receive here at Tierra is for RAID 0 recovery. It is often the case that those clients who need it did not even realise that they had a RAID 0 the first place. The RAID 0 setup is found on external hard drives which (often unknown to [...]

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Why Data Recovery Services Don’t Like it When you Open Your Hard Drive at Home

When your failed hard drive is making a clicking sound or perhaps isn’t spinning up at all but is making a beeping noise there can be a strong temptation to open the drive itself, take the advice that would be offered by all data recovery services; don’t do it. Perhaps the thinking behind the desire [...]

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RAID Data Recovery, Why is it Needed?

RAID 5 is one of the most widely used means of protecting vital data against hardware failure, so why might you find that you need RAID data recovery? How Does RAID5 Protect Against the Need for RAID Data Recovery? A RAID5 is composed of a minimum of 3 individual physical hard drives. Any single one [...]

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Photo Recovery from a Hard Drive

The purpose of this article is to give some guidance regarding what to do and what not to do when you need to carry out photo recovery from your hard drive. When it comes to data recovery, photographs are top of most peoples’ priority list as they are of course the most difficult to replace. [...]

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File Recovery Software

  Probably the single most commonly conducted type of do-it-yourself home data recovery involves attempting file recovery using commercial data recovery software. The purpose of this short article is to give some advice regarding how to proceed with such work. It has been prompted by the regular receipt in our labs of hard drives which [...]

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