Recovering Deleted Data

In the vast majority of cases, deleted data is actually still lurking around on your hard drive. If you put data in the Recycle Bin or Trash, and them empty it, all you are actually doing is telling the system that it can reuse those parts of the disk when it wants. Until you replace those areas with new data, the old data will still be there.

Recovering Deleted Data

The Filing Cabinet

The tried and trusted analogy is of a filing cabinet. When you delete a file, you are removing the index card from the front of the drawer, but the actual file is still in there.

This is why it is really important to switch off your computer as soon as possible if you have accidentally deleted some files. You may not realise but even small actions like checking e-mail or browsing the internet can write cache files to the disk. That is when data could be lost.

Overwritten / Deleted Data

We often hear about the FBI being able to recover overwritten files. While this may have been possible on very old – low capacity hard drives (~100MB), it is unlikely to be possible on modern hard drives. The magnetic material is far too densely packed. Even then, it would only be tiny fragments of data recovered, and not whole files.

The Problem With SSDs

Solid state drives bring a whole new problem of their own. Due to the way the data is distributed around the device, known as wear levelling, you can never be sure of which sector you are writing or overwriting. Wear levelling is necessary to prolong the life of an SSD, but it means the drive could be moving data around behind the scenes, making deleted files much more difficult to track down.

Specifics

In most cases, we can recover deleted files with the original file names and folders. With deleted Mac data, this is often not possible. In that case we have to use a special type of scan, which finds all files of a given type and saves them to numbered files. This means camera photos may be recovered into a JPG folder, with files named like photo0001.jpg, photo0002.jpg and so on.

If required we can process certain types of these files into more meaningful order. For photos we can arrange into folders by date taken, and for music files we can arrange into Artist / Album order.

The Important Bit

If you accidentally delete some files, they are likely to be recoverable. It’s the actions you take next which can make the recovery difficult – if not impossible.

Why RAID Can Be Bad For Business

RAID is often touted as the silver bullet in data storage. Increased storage capacity, resistance from hardware failures and improved performance. While these are all valid upsides to a RAID setup, there are also a few downsides which need to be addressed.

1. Extra Storage.

RAID can allow for a huge pool of storage, but with that storage comes great responsibility. You should factor in at least enough capacity to backup the RAID data somewhere else. If you can only afford 8TB of storage then you should only use 4TB for data and the other 4TB to back it up; Preferably on another machine / standalone system.

2. Redundancy.

The first letter in RAID stands for redundancy. This means you can afford to lose a certain number of disks without losing access to your data.  This also means that if you have a disk failure you need to get it replaced immediately, otherwise you’re running without redundancy.

3. Downtime.

Nobody likes downtime. If your 16TB RAID array goes offline without a backup then you have a couple of options. One option is to attempt to get the RAID back online by replacing disks, rebuilding the array etc, but this is risky. If this is your only copy of the data then rebuilding / reformatting the RAID could corrupt the data beyond recovery. Don’t do this if you don’t have a backup to fall back on.

The second and preferable option is to get the RAID professionally recovered. When we receive a RAID, the first thing we do is make images of all disks. This allows us to work on the RAID without risk. Then we use a read-only process to extract the data onto another form of storage. This is where downtime comes in. Unless you go for an emergency process, you could have to make do without the data for a number of days.

So What’s The Way Forward?

It’s one word. Redundancy.

Whatever you do, make sure your data is replicated across as many types of storage as possible. In an ideal world you would have a duplicate system running alongside the live system, which can take over if anything goes wrong. Then have the data on another type of storage, which you can access from somewhere else. Imagine if the RAID controller failed, and you could only access the data from that one machine.

It doesn’t matter how many backups you have if they all require the same system to access them.

I’ve only just scratched the surface here, but you should always look to make extra copies of your data. It may seem redundant now, but when your server fails containing all your data, all your accounts, all your client details and your website, you’ll be glad you kept that extra copy.

Old Quantum Pro Drive 250 MB 50 Pin SCSI

Old Quantum Pro Drive 250mb 50pin SCSI

This hard drive was opened in our clean room for internal rework. In the process we found that the rubber crash stops attached to the VCM magnet were perished.  They were oozing sticky rubber solution contaminating the drive internally. A word of warning to anyone who may still have one of these hard drives with critical data. I would recommend back up and replacement. This particular hard drive was from a synthesiser that had stopped working.

Bang Goes The Theory Data Recovery

Bang Goes The Theory – Series 6 Episode 3 – March 26th

Bang Goes The Theory Data Recovery

I love Bang Goes The Theory. I loved the alcohol powered motorbikes last week and find it a good doorway into ideas, which are presented in a fun and interesting way. I was extra excited when I started watching episode 3, and relised they would be featuring data recovery. A perfect opportunity to dispel some common myths, and dish out a bit of advice in the process.

Deletion

The data recovery guy Rob, made a good analogy when he described deleting data as ripping out a page from the table of contents. That is pretty much how it works, and really simple to understand.

Data Recovery Experts

Yes they are the world leaders. I’m not going to dispute that, but I’m also not going to name them. They don’t exactly need the extra publicity. It’s worth noting that any decent recovery firm would have reached the same results from the batch of damaged drives.

Getting Physical

I do have a couple of problems with the way some of the drives were “destroyed.”

  1. Sledgehammer. This would have been a good way to destroy a drive, but only if it had been removed from the PC first. Effectively the metal PC case acted like armour, thus protecting the drive from the brunt of the impact.
  2. Tractor. Same as above. If the drive was bare, and on solid ground, then maybe the tractor would have done more damage. Instead, the PC case protected it sufficiently and all the data was recoverable.
  3. Golf Swing. This was great in the example shown, but is a bit unreliable. If you only hit the edge, or if the disk didn’t have glass platters then it may have been recoverable. Maybe take it apart first, then you can see if it’s damaged.
  4. Tea Damaged USB Pen. This was a good one. Solid state storage should survive liquid damage, as long as it is powered off at the time. When dried out, there is a good chance of getting the data back. The worst thing you could do is plug in a wet drive, as this would cause an electrical short, and potentially damage the electronics of the device, and even the computer you plugged it into.
  5. Big Magnet. This was a good one, and surprisingly effective. Only problems are the fact that most people don’t have a giant magnet, and unless you test it afterwards, you wouldn’t know if it had worked.
  6. Toaster. This is an interesting one for me. Of course the toaster damaged the PCB (circuit board) of this hard drive. These drives were quite old, so that was no major problem. If however these were more modern drives the story could have been quite different. A lot of newer drives encrypt the data using keys stored on the PCB. If you melt that PCB, then you have a very difficult job on your hands.
  7. Torched. 100% successful. If you can see the drive destroyed, then that’s perfect.

Optical Discs

Liz later made some good points about the reliability of CD / DVD storage. I agree that although the quoted life spans of DVDs are enormous, in reality DVDs often only last for a couple of years. We have had discs in for recovery that have been stored in temperature-controlled server rooms that have still failed well short of their estimated lifespans.

Hard Disks

Hard disks can last for ages. We have some here that are well over 15 years old and still going strong. The problem is that they can fail without any warning. It is sound advice to backup one drive with another, and then another. This is the only surefire way to avoid being stung by a failed drive. Dallas made a good point of moving one of the backups off site, which is also a good idea.

Scrambling Software

I didn’t like the scrambling advice given near the end. There are problems with the way hard drives are designed, which can prevent the software from accessing bad sectors, and hidden parts of the disk. Although only small parts of the disk, you could leave enough data there to be targeted by fraudsters or whoever.

I advise a two pronged approach. First erase / scramble the data, then physically destroy the drive. This makes it far less likely that your data could end up in the wrong hands.

Summary

It is good to see this sort of thing on mainstream TV, and the advice given was a good starting point for most people. Despite my points above, it was basically a good show: Interesting and informative, with a decent amount of good info.

Many people have little or no knowledge of the way their data is stored, so any way to bring this to their attention is good in my books.

Hitachi Model HTS5450 Notebook Hard Drives

Hard Drive Data Recovery

If you have a failed Hitachi hard drive, you may be interested in our Hitachi Data Recovery Services. We have been receiving Hitachi HTS5450 hard drives for data recovery since 2010. The majority of them appear to show a similar failing symptom, resulting in access to the data becoming more and more difficult.

After experience recovering several of these hard drives we have discovered that the problem appears to be trouble reading from the disc media. This may initially have been caused by the internal read and write heads writing bad data or the disc media itself suffering some mis-alignment or deteriorated magnetic coating.

Whatever the cause, the rework to overcome this can be a slow and very deliberate process. Anyone with one of these hard drives should make sure to back up regularly and any signs of slow or difficult access, you may want to think about replacing the drive.

If you have a failing 5450 drive, then it is important that you don’t try to fix or repair the drive in any way.  It will make things much worse. First try to copy off important files. If that doesn’t work then it may already need a professional recovery process.

Seagate Full Disk Encryption FDE

Seagate FDE hard drives encrypt the data automatically as it is read and written to the drive. As you save data to the drive it is encrypted immediately and can only be accessed when you input your user name and password. The drive will then be temporarily unlocked and allow the operating system to boot. Once the drive is powered off, it will be automatically locked again.

We have received several of these drives from customers who cannot access their data due to a hard drive failure. You may still be asked for the password, but the laptop will then fail to boot. This can be as a result of bad sectors or electronic problems. We can overcome virtually any type of failure and can return your data back to you decrypted and fully accessible on a new hard drive.

See our Seagate Data Recovery Services for more info.

5 DIY Data Recovery Tips

There is never a good time for your hard drive to fail. It always happens when you have something urgent to work on. Before you start frantically trying to gain access to your data, take a deep breath and read our top 5 things to look out for. It could just save your files.

  1. Don’t assume that recovery software will work on your failed hard drive. If your computer cannot see the drive then neither will the recovery software. Some drives need more than software to get the data off in good condition.
  2. Don’t put the drive in the freezer. This myth has been floating around the internet for years, but no real data recovery has ever required a freezer.
  3. Don’t run Checkdisk, Scandisk, Spinrite, Disk Warrior or anything that could WRITE data to your failing drive. If the drive is failing then you could be accidentally overwriting the data you want back.
  4. Don’t try swapping the PCB from one drive to another. A once-simple fix (circa 1990) is now very unlikely to work. Most of the firmware to control the drive is actually stored on the disks, so swapping the card won’t work. Also most drives now have unique PCB information which varies from drive to drive. We usually have to adapt a replacement PCB to make it work with another drive.
  5. Don’t panic. The data is probably recoverable. If the drive has just failed and you haven’t tried any recovery software there is a good chance that we can get back all of your data.

Contact us via the form on the right, or have a look at our different service levels here.

Warning to customers with new WD hard drives

We Recovered a Western Digital Hard Drive That Others Couldn't

Newer WD External drives come with password protection and 256-Bit encryption as standard. Even if a password is not set the encryption is still applied to the data written to the drive. The 256-Bit encryption is controlled by ROM on the USB controller. On portable USB powered hard drives the encrypted ROM is on the actual hard drive. On external desktop drives the ROM is on the interface controller within the external case.

Make sure you keep hold of the external case the hard drive was in. Although not always needed, it could be  important later on. If you’ve lost data, have a look at our Western Digital Data Recovery service.

What’s The Best / Most Reliable Hard Drive?

We get asked this question a lot. The simple answer is that there is no such thing as a reliable hard drive. This is nothing against the hard drive manufacturers, but all drives will fail eventually. Hard drives are delicate machines and must be treated with care. They are not designed to be the one and only storage for all your work, photos and videos. Imagine your computer never booting up again, and then imagine it happening during the most important job you have ever done. That’s how bad it could be, and often is for a lot of people.

A good lifespan for a hard drive is now probably around 3-5 years. In reality we often see hard drives that are only a few months old. If you’re a gambler then maybe you have got away with it so far, but is it really worth the risk?

Backup your data. Maybe then you won’t need to find out how good we are at recovering it.

Read more about backing up your data here