Most corruption is damage to the map rather than the data — the entry describing where a file lives, not the file itself. That is why so much of it is recoverable, and why the standard remedy of letting a repair tool tidy the volume is the thing most likely to make it permanent.
$ bdr diagnose /dev/sda → Device: WD My Passport (2 TB) · external → Status: CORRUPT — file system RAW, data intact → Client: confidential · Reading RG1 $ bdr engineer-working → Forensic image: taken · originals untouched → File system: rebuilt from NTFS structures → Restored: 2,840 folders · 61,200 files $ bdr verify → ✓ documents — 38,400 files → ✓ photos — 22,800 files → ✓ drive readable again — recovered
chkdsk and Disk Utility exist to produce a consistent file system, not to preserve your data — they discard entries they cannot reconcile. If the files matter, copy off whatever still reads before letting anything repair the drive.
These sound the same to the person affected and need completely different handling.
Whether a partially damaged file is usable depends almost entirely on what kind of file it is.
Office documents and ZIP archives are internally compressed containers, so damage in one area frequently makes the whole file unopenable — but the structure is well documented and the intact parts can often be extracted and repackaged. Photographs and video tolerate loss gracefully: a JPEG missing its tail renders partially, and video containers can be remuxed to play up to the damage and beyond it.
Databases are the least forgiving — a corrupt page in the wrong place can make the whole file unmountable, and repair means working with the internal structures rather than the file as a whole. Plain text, CAD and RAW images generally recover well, because damage tends to affect a bounded region rather than the whole.
The order matters more here than almost anywhere, because the standard fixes are the risk.
Widespread corruption usually means hardware — bad sectors spreading. Isolated corruption after a crash usually does not. The diagnostic settles it before anything is attempted.
The drive is cloned before any repair, so every subsequent attempt runs against a copy and nothing can be made worse.
Master file table, APFS checkpoints or ext superblocks are reconstructed from surviving copies, which frequently restores filenames and folders along with the data.
Where the file system cannot be rebuilt, files are extracted by signature — contents recovered, names and folders not.
Recovered files are opened in their applications. Anything that still fails is reported by name rather than returned as a file that opens to nothing.
Priced by device, not by how many files come back.
A single drive, SSD or external is from £300 +VAT; memory cards and USB sticks from £250 +VAT; RAID, NAS and server volumes from £500 +VAT. Free 48-hour diagnostic and a written quote before any work, with most jobs no fix, no fee.
Tell us which files matter most. On a partial recovery it is far more useful to confirm the right material has come back than to hand over a large number of files and leave you to check.
Send the device in for its free diagnostic and tell us briefly what happened; an engineer reviews it and confirms your exact quote in writing before anything starts.
Getting your data back begins with getting the device to us. Pack it up safely, pop your contact details inside, and send it over — once we’ve run the free diagnostic, we’ll confirm your exact price in writing before any work starts.
Posting it? A tracked, insured service is what we’d recommend. Rather drop it in? You’re welcome Monday to Friday, 9am to 5:30pm — just package the device up as above first.
Want a bit more detail first? Fill in the form with more about your issue and an engineer will review it and send you a custom quote.
We’ll be in touch shortly. If it’s urgent, call 01865 593000.
What people most often ask about recovering corrupted files and drives.
Isolated corruption after a crash or bad ejection is usually the file system. Widespread corruption, files failing progressively, or a drive that has become slow points at bad sectors spreading — which is hardware. The free diagnostic distinguishes them before anything is attempted.
Not before copying off what still reads. chkdsk aims at a consistent file system rather than your files, and where it cannot reconcile an entry it deletes or truncates it. On a failing drive it is the likeliest single action to make the loss permanent.
That Windows cannot identify the file system, usually because the boot sector or master file table is damaged rather than because the files are gone. Don’t accept the offer to format — that writes a new structure over the one recovery would use.
It depends on the type. Photographs and video tolerate loss and often remain usable; Office documents and archives are compressed containers where damage can make the whole file unopenable, though intact parts can often be extracted; databases are the least forgiving.
If the file system can be rebuilt, yes. Where it is beyond repair, files are carved by signature — contents come back correctly but named sequentially without folder structure. We’ll tell you which applies at the diagnostic.
From £300 plus VAT for a single drive, £250 plus VAT for cards and USB sticks, and from £500 plus VAT for RAID, NAS or server volumes — fixed in a written quote after a free 48-hour diagnostic.
A free diagnostic, no fix no fee on most jobs, and corruption recovery from any drive, stick or card. Leave the repair tools alone — start your recovery today.