A surveillance drive reporting SMART failure, in a recorder that had been quietly flagging it. The warnings went unseen for the ordinary reason: nobody opens a DVR interface until something has happened and they need the footage.
A break-in, and a CCTV system that would not give up the recording of it. The recorder was reporting a drive error and refusing to play back; connected to a computer, the disk appeared unformatted. Inside was a Seagate SkyHawk — a surveillance-grade drive, doing exactly the job it was built for, and worn out from it.
SMART had been reporting a failing drive for some weeks. That information had been sitting in the recorder's own interface the whole time, which is the practical problem with surveillance storage: nobody logs into a DVR when everything is working. The system is checked on the day it is needed, which is the worst possible day to discover the disk is failing.
The drive was degrading rather than dead — reallocated sectors in quantity, a pending count still climbing, and read times long enough that the recorder had given up on it. Surveillance drives live a harder life than almost any other: continuous writes, 24 hours a day, often in a warm cabinet with no ventilation and no maintenance for years.
Two things were in our favour. The platters were not scored, so this was wear rather than mechanical failure. And the recorder had stopped writing when it flagged the error, which meant the loop had halted — the footage from the night in question had not been overwritten.
The disk was imaged read-only in graduated passes: a fast sweep first to capture everything that read on the first attempt, then repeated passes over the weak regions with longer timeouts. Unreadable sectors were logged rather than retried indefinitely, because on a worn drive persistence costs more than it returns.
From the image the video had to be located by structure rather than read as files. Recorders write in proprietary formats with no conventional directory — a continuous ring of interleaved camera streams with timestamps embedded in the data itself. The recording layout was analysed, the requested window located by timestamp, the relevant camera separated from the others written alongside it, and the frames reassembled in order.
The footage was exported as MP4 so it plays without the manufacturer's software — which matters when it is going to an insurer or the police. Timestamps were preserved and visible in the output, and a wider window either side of the incident was supplied as well, since the exact moment is rarely where people first think it is.
The break-in footage was recovered and handed over in a usable form.
The wider lesson is about the warning nobody received. A surveillance drive is the hardest-worked disk most premises own, it is checked least often, and its health reporting lives behind an interface nobody opens. If a system matters for evidence, the drive is worth checking on a schedule rather than on the day something happens.
Surveillance drives write continuously, often for years in a warm cabinet, and they report their own health into an interface nobody opens. By the time a recording is needed, a failing drive has usually been saying so for weeks. Check the drive status periodically, and if the recorder flags an error, take the disk out of service rather than leaving it recording. CCTV, DVR and NVR recovery is £800 +VAT flat with a 50% deposit, after a free 48-hour diagnostic.
Get the device to us for a free diagnostic and a quick note on what went wrong — an engineer looks it over and puts your exact quote in writing before anything is started.
The route to your data starts with the device reaching us. Box it up securely, tuck your contact details inside, and send it across — after the free diagnostic, we put your exact price in writing before a single step is taken.
Sending it by post? Go with a tracked, insured service. Prefer to bring it round? Our door is open Monday to Friday, 9am to 5:30pm — just pack the device as described above beforehand.
Prefer to get a sense of things first? Complete the form with a bit more about the fault and an engineer will look it over and send back a tailored quote.
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Usually not. A drive reporting SMART failure is degrading rather than dead, and the footage is generally still present. Take the disk out of service immediately — if the recorder keeps running it may resume overwriting, and that is what actually loses the recording.
Because the health reporting lives in the recorder’s own interface, and nobody opens a DVR when everything is working. Surveillance drives are the hardest-worked disks on most premises and the least monitored, which is a poor combination.
No. Recorders write video in proprietary formats with no conventional file system, so Windows cannot recognise the disk and assumes it is blank. Formatting writes over the footage. Decline the prompt and disconnect it.
Yes, and telling us in advance helps. Timestamps are embedded in the video structure, so a particular window can be targeted and a single camera separated from the others recorded alongside it. We supply a wider window either side as well.
£800 plus VAT flat, confirmed after a free 48-hour diagnostic. This work carries a 50% deposit and sits outside no fix, no fee, because the effort of reverse-engineering an undocumented recorder format is the same whether or not the footage survived.
Kick off with an instant online quote, or ring us and talk it through first. Either way you’ll know a clear, fixed price before any work starts.