An estate agency’s Samsung EVO SSD would let files be read but not saved, changed or deleted — property listings and contracts frozen in place. That’s an SSD protecting itself: its NAND flash had worn out, and the firmware had dropped to read-only to stop any further writes. Handled correctly, read-only is the best state a failing SSD can be in for recovery. We imaged it before it could deteriorate and rebuilt the files.
A busy estate agency ran its working files from a Samsung EVO SSD — property listings, floor plans, signed contracts and client records. One day the drive stopped accepting changes: documents opened and could be read, but nothing could be saved, edited or deleted, and both Windows and macOS refused to write to it, even though diagnostics reported the drive as ‘healthy’. It looked baffling — a healthy-looking drive you simply can’t write to — but it’s a specific, well-understood SSD failure, and the agency did exactly the right thing by stopping and sending it in rather than trying to reformat or force it.
An SSD stores data in NAND flash memory, and NAND has a physical limit that spinning disks don’t: each memory cell can only be erased and rewritten a finite number of times — its program/erase (P/E) cycle count. Every write wears the cells a little. To spread that wear evenly the controller uses wear levelling, and it keeps a pool of spare blocks in reserve to replace cells as they fail. Over years of heavy use — or on a drive that’s been written to hard — the cells reach their limit and the spare pool is used up. At that point the NAND can no longer be trusted to hold new data reliably, and the drive is, in effect, worn out. This EVO had reached exactly that stage.
Read-only mode isn’t a malfunction here — it’s a safety catch. When an SSD controller detects that the NAND has worn past a safe threshold or that it can no longer guarantee writes, its firmware deliberately switches the drive to write-protected, read-only mode. The logic is sound: further writing to worn cells risks corrupting the data that’s still there, so the drive locks itself to preserve what it holds and give you a chance to copy it off. Counter-intuitively, that makes read-only one of the more recoverable SSD failures — the data is intact and stable, provided it’s read carefully and nothing tries to force writes or a format onto the drive, which is exactly what can tip it from read-only into unreadable.
Sometimes, on a cleanly read-only drive, files can be copied straight off — but there’s a catch that makes professional imaging the safer route. An SSD doesn’t store your data in a simple line the way a hard drive does. The controller keeps a constantly-updated map called the Flash Translation Layer (FTL) that translates the logical addresses your computer asks for into scattered physical locations across the NAND, while handling wear levelling and bad-block management underneath. On a worn drive the FTL and the controller are themselves under strain, and casual copying can stall, drop the drive offline, or miss data. Reading the whole drive once, gently and completely, through proper imaging tools captures everything in a stable form before anything degrades further.
Because the SSD was still presenting in read-only mode, it was imaged sector by sector through a write blocker — a forensic, bit-for-bit clone that could never alter the original — capturing the complete logical drive while the FTL was still cooperating. Where the worn NAND had introduced bit errors, the drive’s error-correcting codes (ECC) were applied to correct them and recover clean data, and any file-system inconsistencies left by the drive going read-only mid-use were repaired on the image. That restored the NTFS structure so the agency’s folders and files could be located and named correctly, rather than pulled back as anonymous fragments. Every step after imaging happened on the copy, leaving the worn drive untouched.
The recovered documents, listings, contracts, financial records and property images were opened and checked for integrity before sign-off, then written to a new SSD so the agency wasn’t handed back the worn one, and returned. The lesson we passed on matters for anyone relying on an SSD: they don’t last forever, and they often give little warning before wear-out — so a drive that’s several years old and heavily used should have a current backup, and if an SSD ever goes read-only, the safest response is to stop, leave it exactly as it is, and get the data imaged rather than trying to force it back into service.
Forensic sector imaging through a write blocker · ECC-based bit-error correction on worn NAND · NTFS file-system repair on the image · verification and transfer to a fresh SSD. Where an SSD no longer presents at all, chip-level NAND reading and FTL reconstruction are used instead. All work in-house at our Belfast lab.
Don’t reformat it or try to force writes — that’s what turns a recoverable read-only SSD into an unreadable one. Send it in for a free, no-obligation diagnostic. We’ll tell you what can be recovered and put a fixed price in writing before any work starts, and on most jobs it’s no fix, no fee. We recover Samsung, Crucial, WD and other SSDs for customers across the UK.
That’s classic SSD read-only mode. When the NAND flash wears past a safe point, the controller switches the drive to write-protected to stop further writes corrupting your data. Diagnostics can still call it ‘healthy’ because the drive is doing its job — protecting what’s there. The data is usually intact and recoverable, as long as nothing tries to reformat or force-write the drive.
Usually yes, especially from one that’s gone read-only, because the data is stable and can be imaged before it degrades further. Even an SSD that no longer presents to a computer can often be recovered by reading the raw NAND chips and rebuilding the controller’s translation layer. The key is to stop using it and avoid any attempt to reset or reformat it.
It depends on how much they’re written to, but SSDs have a finite write endurance and often give little obvious warning before wear-out — read-only mode may be the first clear sign. That’s exactly why an older, heavily-used SSD should have a current backup: by the time it locks itself read-only, it’s telling you it’s near the end of its writable life.