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Three Partitions, One of Them Unreadable

A self-employed video editor in Bromley keeps a second disc in his machine split into three: one for projects, one for exported masters, one for stock footage. Two of them still mount perfectly. The middle one, the exported masters, went unreadable overnight. A shop he described the problem to suggested deleting the partition table and letting Windows write a new one, which is roughly the opposite of what the situation needed.

Hard DriveCorruption / Filesystem
// the job in four lines
MediaA secondary internal drive from a Windows machine divided into three partitions. Two mount and read normally; the third is unreadable and holds exported master files.
What was reportedSecond internal disc out of a Windows 8 desktop, split three ways, two of the three still mount normally, the middle one unreadable, owner suspects the table, a shop advised wiping and recreating it, exported masters wanted.
Fault classLogical, and local to one partition. The disc was mechanically sound, which the two working partitions demonstrated. The affected partition's entry and the front of its own index had been damaged, so it could not be mounted while its neighbours were unaffected.
On the benchRead behind a hardware write blocker with nothing written and no table altered, imaged on DeepSpar behind PC-3000 UDMA, the partition table and the affected volume's master file table parsed from the image in R-Studio and cross-checked in UFS Explorer, the damaged entry and index reconstructed on the copy, exported masters carved by content signature where records could not be rebuilt, everything validated by playing it and written to fresh media.
// reading the fault

Reading the fault

The two working partitions do most of the diagnosis for you. If the disc were failing mechanically or electrically, nothing on it would mount. Two out of three reading normally proves the mechanism, the electronics and the firmware are all fine, and narrows the fault to structures belonging to the third.

A partition table is a small list, and small lists are fragile. A handful of entries at the very start of the disc describe where each partition begins and how long it is. Damage one entry and one partition vanishes while the others carry on, which is precisely the pattern he had.

Deleting the table would have been an expensive suggestion to follow. Recreating a partition table writes new entries and, depending on the tool and the choices made, can write a new filesystem header on top of the old one. On a drive where the goal is to reconstruct the original entry, replacing it with a fresh guess destroys the information needed to do that.

Rebuilding on a copy makes the whole thing reversible. Candidate boundaries can be tried and rejected as often as necessary against an image, and the right one is identifiable because the filesystem behind it resolves and the files open. None of that experimentation touches the original disc, which is what makes it safe to experiment at all.

// bench work

Bench work

The disc went behind a hardware write blocker with nothing allowed to write to it, and was imaged on DeepSpar behind PC-3000 UDMA in one pass. It profiled as healthy throughout, with a short defect list and no slow regions, which was consistent with two partitions still working.

R-Studio parsed the table from the image and found the middle entry damaged. The partition's own boundaries were re-derived by locating its filesystem header and its backup, then cross-checked in UFS Explorer before anything was accepted. With the entry reconstructed, the master file table was rebuilt from its mirror, and the exported masters that remained unreferenced were carved by content signature. A sample from each project was played through before the set was written to fresh media.

// what went back

What went back

All the exported masters came back, together with the folder structure he files them in by client and date. The two healthy partitions were left alone throughout and were never part of the job.

One drive, £300 + VAT, regardless of how many partitions are on it. Nothing was opened and no part was replaced, so this was logical work and no fix, no fee applied, with the invoice following his confirmation that the files played.

One partition gone and the others fine

Leave the disc alone and do not touch the table. Any suggestion that begins with deleting and recreating the partition should be declined, however confidently it is offered, because the original entry is the thing that has to be reconstructed and overwriting it makes that harder. Do not run a check on the affected partition, and do not assign it a letter and let Windows initialise it. Keep using the two that work if you must, but ideally power the machine down, since anything writing to the disc risks landing in space the damaged partition occupies. The reconstruction is done against an image, where a wrong guess can simply be thrown away.

Reading this and recognising your own drive? Every job on this page started the same way. Examining the media costs nothing, the examination closes 2 working days after the parcel is booked in and not sooner, and what comes out of it is a single figure in writing that then stays where it was put. A finished single-drive recovery leaves here 2 to 4 working days after that. Payment follows one published sentence: no fix, no fee all jobs except electronic and mechanical failures, chip level work, DVR and Forensic jobs. Deletions, damaged file systems, lost partitions, firmware and service-area repair therefore all carry the guarantee. Physical work does not: a drive opened under laminar flow, a repair to a board or to a memory chip, liquid or fire damage. Those take 50% of the quoted figure before anything starts, and the remainder falls due only if your files come back. The figures themselves are short: a memory card, a USB stick or a pen drive is £250 + VAT, any one hard drive or SSD including NVMe is £300 + VAT, and arrays, NAS boxes and servers are quoted from £500 + VAT. Recorder disks, BitLocker volumes and forensic work are quoted apart from those and settled in advance. Where the storage is bolted inside a laptop, a tower, a Mac or a server, free it and post the bare unit: taking machines apart is not work this lab does, and flash soldered flat onto a mainboard, which is how Apple Silicon Macs and a good many thin ultrabooks are built, cannot be taken in at all. Nor can phones or tablets. If it unscrews or unplugs, it is our sort of job. Send it tracked and insured to Guildford Data Recovery, Building 2, Ground Floor, Guildford Business Park, Guildford GU2 8XH, or book a courier yourself; the Guildford reception also takes devices in person, Mon–Fri 9:00am–5:30pm. Nobody collects, and there is no counter in Bracknell to call at. Freephone 0800 689 0668. Packing notes and the shipping form live here.
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These files are written up from genuine enquiries taken from households and businesses in Bracknell, across Berkshire and Surrey and into London, with names, firms and anything else identifying stripped out. Each one sets down how the fault was reasoned through, the method it actually needed and the equipment it was worked on. One of them is a job that was turned away, which belongs here as much as the rest of them.

// nearby on the shelf

Three more files along the same lines

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