The cause · someone formatted it
The calls sound alike wherever in Plymouth, Devon or Cornwall they come from: somebody hit Format on the wrong disk. It is nearly always the quick kind, which exchanges the index and leaves the files precisely where they were — as data loss goes, the mild variety. A full format taken to the end is a different story, and we would rather say so on the phone than after a parcel has arrived in Bristol.
You will be talking to an engineer
0800 6890668
| What happens | What that points to | What to do |
|---|---|---|
| Windows offered to format the disk and you said yes | A fresh, empty index sits over the old one | Leave it be — the files are still underneath |
| The drive opens with nothing in it, and every byte shows as free | Only the listing was replaced; what it pointed at has not moved | Add nothing further to it |
| A full format run to the end | From Vista on, a full format drops a zero into each sector, and a zero holds nothing | There is nothing to read |
| A full format stopped halfway | Whatever the zero pass never got to is intact | Halt it and cut the power |
| diskpart clean | Removes the partition table, nothing more; the volumes beneath remain | Usually readable |
| diskpart clean all | Puts zeros across every sector, the same result as a full format allowed to finish | Nothing to be read |
| An SSD, quick-formatted | TRIM has gone off and the controller is emptying cells unaided | Switch it off now |
Whatever arrives is booked in under a case number on the day it reaches the bench. An engineer then works out the actual fault, and that part is free. You get a plain answer on what can come off the drive and what cannot, followed by one price in writing. Nothing further happens until you have read it and agreed.
Which of the four was it — quick format, full format, clean, or clean all? And did it get to the end? That sets a hard ceiling on what can be read back, so an engineer establishes it before anyone discusses chances.
All of this happens on the image and never on the disk. Whatever remains of the previous file system is recovered from underneath the new one and reassembled. Given enough readable records, the files return under their own names and dates, in the folders they lived in.
Where nothing structural survives, files are identified by the header bytes their type opens with and pulled off the image whole. Anything still pointing at a file restores its name.
Thinking it over costs you nothing. Everything the drive gave up is listed for you before any invoice exists, and the bill only follows your go-ahead. Files travel back on media bought in for your job, with return carriage paid at this end, and the case stays on the bench until you confirm they open on your own computer.
Put plainly: where nothing but a quick format ran, the outlook is good. Where a full format finished, or clean all went into diskpart, there is nothing on that disk to hunt for — a zero was written deliberately into every sector, and Windows has behaved that way since Vista. Any firm telling you a completed full format can be reversed should be asked to explain the mechanism.
Two 2TB disks of the same model were sitting in the one tower, and the format landed on the one carrying the family archive instead of the spare. A quick format writes a fresh index and leaves the rest alone, which is the only reason any of it survived. Nothing new had been saved to the disk in the meantime, so the archive came out exactly as it went in.
Normally all of it. On a hard disk a quick format lays down a fresh, empty index and goes no further; the sectors themselves are left alone. Your files are exactly where you put them, beneath a catalogue that has stopped listing them. Add nothing to the disk and most folders return with names and dates intact.
It can, but only a full format that ran to completion. From Vista onwards every sector has a zero put into it as the pass goes by. A quick format writes not one. That single distinction decides most of these jobs.
Turn the machine off. Do not put the disk back into use; let an engineer image it before anything else happens. Every file saved from now onwards settles over something that was still readable.
It does not. Quick-format an SSD and TRIM generally fires, after which the controller clears the freed blocks under its own steam. Take the power off and ring. Among all the format jobs that reach this bench, this is the one where delay costs the most.
The diagnosis is free, and it comes back as a list: which files read, which do not, and what getting them off would take. Until then, leave the drive unplugged.