The camera recorded it, and then the recorder failed, or the loop came round and wrote across the week that mattered, or somebody reset the unit while having a tidy up. Surveillance video gets carved back off DVR and NVR disks here for households, shops, farms, insurers and legal teams throughout Norfolk — including the yards and packhouses where a camera is very often the only witness on site.
Every cctv / dvr job is diagnosed free. The quote follows in writing, fixed, before a screwdriver is picked up.
No fix, no fee all jobs except electronic and mechanical failures, chip level work, DVR and Forensic jobs. Full pricing is on the data recovery cost page.
The first job on any cctv / dvr is matching the symptom to the fault — and after twenty-odd years, these thirty account for very nearly everything that comes through the door.
Continuous writing retires surveillance drives early, which is exactly what they were built to endure and still what finishes them. Whatever the platters are still holding gets carved back into something watchable.
Fragments of an overwritten period survive in unallocated space more often than seems reasonable, provided the recording stops the moment somebody realises. Every hour it keeps running costs another hour of the past.
That removes the index and leaves the video streams sitting where they were. Cut the power before the recorder reuses the space they occupy, because it will, and soon.
Recorder power supplies and boards fail around a perfectly healthy disk. It is the most cheerful outcome in surveillance work and a mercifully common one.
An engineer's factory reset blanks the listings without touching the video data underneath. Carving raises whatever that reset never physically overwrote, which is usually the bulk of it.
Hikvision, Dahua and the many rebadges of both corrupt in ways that only format-fluent tooling untangles. Ours has had years of practice at precisely this.
Intruders attack the box on their way out. The disk inside routinely survives the attack and gives its evidence anyway, which is a satisfying kind of irony.
Recorders out of an incident scene are stabilised, cleaned and imaged like any other injured drive. The footage frequently outlives the building it was recording.
Streams reassembled per camera and per timeline, delivered in a playable form with integrity hashes accompanying the bundle so the material stands up to questioning.
The map corrupted and the video did not. The timeline gets rebuilt from the streams themselves, hour after hour, until it plays in order.
WD Purple and Seagate SkyHawk units turn up with heads polished smooth by years of writing without a break. Image first and carve second, never the other way round.
The ST2000VX015 and its relatives fail under the same relentless duty as everyone else's surveillance stock. Filtered-air repair, then the carve.
Hikvision's range and the countless rebadges of it dominate installations around here, and its raw storage layout is mapped in detail at this end.
Some lines bind the drive to the box's own firmware, so nothing gets mounted. The video is carved directly out of a raw capture instead, which sidesteps the whole problem.
Clocks drift apart over months and nobody notices until the footage matters. The drift is measured, documented and corrected so exported timelines hold together under scrutiny.
The recorder falls back to the year 2000 and stamps new footage with a date that never happened. True times are re-derived during the carve rather than guessed at.
Their small cards loop to exhaustion in the same way a recorder's disk does. Worn microSDs cross the corridor to the flash bench for chip-level reads.
Locked cabinets bake recorders every year, and heat-aged platters arrive expecting sympathy. What they get is patient imaging, which works considerably better.
Fitted during a cheap repair, a plain desktop drive collapses quickly under continuous duty because it was never rated for it. Recovered, then replaced with proper surveillance stock.
Interrupted USB exports through the recorder's own menu damage the listings. The streams get recut from a raw image and the menu is left out of it entirely.
H.265 variants leave whole seconds between full frames, so a damaged span decodes patchily. Whatever the mathematics can restore is restored, and nothing at all is invented.
Live view worked and the disk recorded nothing, which is discovered on the day footage is needed. We establish when writing genuinely stopped and give that verdict without softening it.
Two-disk recorders set up to fill one and ignore its neighbour entirely. The loaded drive gets carved; the empty one gets half a minute and a straight answer.
Footage that was never written cannot be recovered by anybody, whatever any website claims. Whatever the sensor did write to disk comes back exactly.
A locked recorder and a phone number that rings out. The disk is entirely indifferent to admin passwords, and the footage carves straight off the platters.
Larger recorders spread their video across several disks, and losing one leaves the rest holding fragments that no single drive can make sense of alone. All the members are imaged and the arrangement is solved before any carving starts, exactly as with any other array.
Recorders often export in their own format alongside a small player that was written for Windows XP and has not been updated since. The file is fine. Getting it into an ordinary player is a conversion job, and it is one we do routinely.
Fit a 10TB drive to a recorder that was only ever tested with 4TB and it may address a fraction of it, looping over that fraction and overwriting far sooner than the settings claim. Owners find out when they go looking for last month.
Lightning does not need to hit the building. A strike near a run of camera cable, especially on open ground, puts a spike into the recorder through the camera inputs and takes the board and often the drive electronics with it. Board repair with the ROM carried over is the usual route.
Surveillance file systems are nothing like Windows file systems, so Windows reports the disk as raw and offers to format it. Accepting that writes a new structure over the footage. Declining costs nothing, and the drive should then go to a bench rather than into another machine.
Hikvision, Dahua, Swann, HiLook, Annke and the long list of rebadged units sharing their boards each lay video down in their own fashion, generally as raw streams written straight to the disk with no file system a normal computer will admit to understanding. Tools on this bench read those layouts directly. Streams are cut out of a full sector-level copy, matched back to the camera channel and the clock they came from, and handed over as ordinary files that play on anything with the original timing preserved. Nobody consults the recorder's own menus or its export function at any point, which is just as well, given how often one of the two is why the footage went missing in the first place.
Video heading for the police, an insurer or a courtroom must be demonstrably intact and not merely watchable. Work runs on hash-verified copies, handling is written down from the moment the parcel is opened until it goes back out, and exports can be issued with integrity hashes of their own attached. Tell us the date and the window of hours involved and the carve is pointed at those recordings ahead of everything else, which saves considerable time on a disk holding months of continuous footage. Pricing is simple and stated up front: £400 + VAT for a standard recorder drive, classed as forensic work, which means settlement before the work rather than on results.
Surveillance work is drive recovery with video forensics laid over it, and both trades sit in this building:
Native parsers for Hikvision and Dahua and the own-brand crowd behind them, turning raw surveillance blocks back into files that play.
Frames sorted by channel and timestamp and joined up into continuous per-camera footage that plays first time rather than after an argument.
Purples, SkyHawks and whatever else a recorder turns out to contain are imaged on the same hardware as everything else in the drive room.
Verified captures, documented custody and integrity hashes for any footage heading to insurers, solicitors or the police.
Recovered material is handed over as ordinary files that open in ordinary players. No codec hunt is required at your end.
The recorder's own disk is never written to at any stage. All the processing happens against the captured image.
Take the lid off most own-brand recorders and there is a Hikvision or Dahua silkscreen looking back at you. The DS-7200 family alone accounts for an outsized share of installations across the city and the market towns around it. Inside, spinning away, are surveillance Purples and SkyHawks such as the ST2000VX015 that have written every second of every day for years without a break, which is why each job opens with an inspection and a complete image before a single frame is carved. Send the drive rather than the recorder where you can — and if the box itself has to come, ring first on 0800 689 0668 and we will agree what travels.
Most of what reaches this bench arrived by tracked, insured post. It is the steadiest way to move a poorly drive, and a parcel posted in Norfolk is usually on the bench the next working day.
Is the drive still bolted inside a laptop, desktop, MacBook, iMac, server or CCTV / DVR recorder? The hard drive or SSD needs to come out first, and only the bare drive travels — taking drives out of machines is not something we do here. Storage soldered to a motherboard (Apple Silicon Macs, one or two very thin laptops) is the single thing beyond us: if it will not come out, it cannot come in.
↓ Print the shipping & booking-in form (PDF)
Mark the parcel for the attention of Cambridge Data Recovery. From Norwich it is about an hour and twenty down the A11, then two minutes off the A14 at Junction 32 — or next working day by tracked post. You hear from us as soon as it is booked onto the bench.
Unsure what to put in the box? Ring 0800 689 0668 before you seal it, or run the free online diagnostic.
Diagnosis free, one figure written down, most work under no fix no fee. Start online, or ring us.