Three classes of hard drive failure
Hard drives can fail in a wide variety of ways, and those failures fall into three main groups. Which group a drive belongs to determines both how it is handled and how good the odds are, which is why classification is always the first step.
Logical damage
The drive spins up and behaves normally, but data stored on it has become inaccessible. In most cases the cause is human error — and these are precisely the cases with the best prospects of a full recovery.
- A file or folder deleted from the disk
- A format performed deliberately or by mistake
- A damaged or deleted partition table
- A system image cloned onto the wrong disk or partition
- A virus or ransomware blocking access to the data
The first step with logical damage, or suspected logical damage, is to make a complete image of the original drive. All recovery work is then carried out on that copy, so that the attempt itself cannot cause further harm to the original. Only then is the imaged data examined and the extraction work begun.
Damage to the circuit board (PCB)
This kind of damage stops the drive functioning. Sometimes the board shorts — in extreme cases there is a distinct burnt smell — and as a result the drive does not power up at all and the motor does not turn. In other cases you can hear and feel the motor spinning, yet the drive still will not present its data. During the assessment we establish the extent of the damage and decide how to proceed.
One warning worth stating plainly: do not attempt to swap circuit boards between drives in order to recover data yourself. Drives run at different operating voltages, and each board carries calibration data unique to the drive it belongs to — an uncontrolled swap can cause further, irreversible damage.
Physical damage inside the drive (HDA)
This covers everything inside the sealed housing: the read/write heads, the motor, and the magnetic platters that hold the data. Recovery here is more involved — the drive has to be opened and worked on in a cleanroom environment, since a single dust particle on a platter surface is enough to destroy it. Cases of this kind are assessed by us and handled in a dedicated clean environment.
Verification after recovery
Once the data has been extracted, everything recovered is checked logically: documents and images are sampled and opened, and mail files and databases are tested for integrity. There is no value in a recovery that returns corrupt files, so this is an integral part of the work.
We recover data — we do not repair the drive
To be clear: our aim is to recover the data alone and copy it to sound media. A drive that has suffered a physical failure will not be returned to service, even where the recovery itself succeeded completely.
What to do the moment you notice a problem
- Stop using the drive and the computer — every further write risks overwriting exactly what you want back
- Do not install recovery software onto the affected drive
- If a drive is making unusual noises, power it off immediately and do not run it again
- Come to us for an assessment before trying anything yourself