Corruption never appears from nowhere. An SD card that suddenly demands formatting, shows empty folders, or hands back gibberish filenames arrived there down one of a handful of well-worn roads — and knowing which one changes both the rescue and whether the card deserves a second life. Causes first, then the rescue, then the repair.
Yanked mid-write. Passed between too many devices. Fake capacity. Worn-out flash. Each leaves its own fingerprint — and caught early, none of them has to cost you the photos.
Interrupted writes top the table. A card pulled while the camera’s buffer is still emptying, a battery dying mid-burst, a phone rebooting during a save — the file system’s bookkeeping is caught mid-sentence, and on the next insert the device can’t make sense of it. Device-hopping is quieter: camera to phone to laptop to smart TV, each with its own notion of how the file system should look, each ‘helpfully’ writing thumbnails and indexes until the structures start to disagree with themselves. Fake capacity is the nastiest — a small chip reprogrammed to claim 256 GB behaves perfectly until you write past its real size, then silently overwrites earlier photos and corrupts wholesale; suspiciously cheap cards from marketplace sellers are the usual source. And plain wear: flash has a finite write life, budget cards use the cheapest grades, and a card that’s been the workhorse for years eventually starts mis-remembering. Different roads — but they all end in the same place, which is why the rescue is the same for all of them.
Stop using the card the second corruption shows — every further write lands on top of your photos’ last known addresses. Connect it to a computer through a card reader (the camera-as-cable route is slower and flakier), turn down every prompt the operating system offers — format, scan-and-fix, initialise, they all write — and run PhotoRec: free, read-only, and built to carve photos and video straight out of the flash whether or not the file system still makes sense. Point its output at a folder on the computer, never at the card, and judge the results by opening files, largest first. Ten minutes of discipline recovers the great majority of corrupt-card cases without spending a penny.
The exception that skips the ten minutes: a card that isn’t detected at all, gets warm, or physically rattles. That’s hardware — controller failure or worse — and home tools have nothing to grip; monolith-level reads on the bench do. Our memory card recovery service starts with the free diagnostic either way.
With the photos verified safe on the computer, the card can be dealt with honestly. A full format in the device it will live in rebuilds every structure and returns most cards to service. But apply the two-strikes rule: corruption that arrived with no obvious cause — no yanked card, no dead battery — is usually the flash itself going, and a card that corrupts twice has told you its plans. Cards cost pounds; reshooting a wedding costs the impossible. Retire the suspects, buy branded from reputable sellers, format in-device rather than in Windows, and treat every card as a courier rather than an archive — photos should move off within days. Formatted the card before reading this and then remembered what was on it? Same carving method, dedicated page: formatted media recovery.
No — and flaky behaviour is the opposite of healing. A card that reads on the third attempt, or works in the camera but not the laptop, is one whose controller or contacts are deteriorating between tries. Each retry is another chance for a half-write to make things worse. Treat the first corruption as the card’s resignation letter: get the photos off, then retire it.
Repeat corruption almost always has a cause you can name. The usual four: the card shuttles between devices that each treat its file system differently; it gets pulled or the battery dies mid-write; it’s a counterfeit whose real capacity is a fraction of the label, corrupting everything written past the true limit; or the flash is simply worn out. A genuine branded card, formatted in the device it lives in and removed only after writing has finished, almost never makes a habit of it.
Not while the photos are still on it. CHKDSK repairs file systems by writing corrections — and its infamous habit of turning damaged files into useless FILE0000.CHK fragments has cost people whole shoots. The safe order is fixed: carve the photos off first with a read-only tool, and let CHKDSK or a format rebuild the card afterwards, when there’s nothing left to lose.
Free 48-hour diagnostic in the lab — an honest read of what happened and whether DIY carving is safe, before anything is put at risk.