SD and microSD cards are wonderfully convenient and slightly fragile — and when one corrupts, it usually takes irreplaceable photos and videos with it. The reassuring news is that a corrupted card is very often recoverable, because the data is normally still sitting in the memory; it’s the index describing it that’s broken. The trick is not to make it worse before you recover it.
A card that asks to be formatted usually still has your photos on it. Formatting throws away what a recovery would use. Stop using the card, don’t reformat, and image it read-only.
Most card corruption is logical, and most of it is caused by an interrupted write: pulling the card out mid-save, a camera or phone battery dying while writing, or removing it without ejecting safely. Each can leave the card’s file system half-updated and inconsistent, so the device can no longer make sense of it. Accidental formatting, a card filling up and erroring, and plain wear on cheaper cards do the rest.
The important point is that these faults damage the file system — the index — not usually the photos themselves. The images are still in the memory; the card just can’t list them anymore.
It shows up in familiar ways: the card “needs to be formatted” before it can be used, the camera or phone won’t read it or reports an error, photos and videos are missing or won’t open, or the card claims to be write-protected. Sometimes it appears on a computer as empty or with the wrong capacity.
Two quick things worth ruling out first. If it says write-protected, check the little lock switch on the side of a full-size SD card (or the adapter a microSD sits in) — it’s sometimes just flicked to locked. And don’t keep reinserting a failing card repeatedly; if it’s struggling, stop.
When a card corrupts, every device offers to format it — and it’s the one thing you mustn’t do if you want the photos. Formatting lays down a fresh, empty file system over the damaged one, discarding the records a recovery would use to rebuild your images. The photos are usually still physically present behind the corruption, right up until you format them away.
So decline the prompt, take the card out of the device, and don’t shoot any more photos to it — new files can overwrite the old ones. Set it aside and recover it properly.
For the usual logical corruption, recovery is very doable. The card is read read-only and imaged to a computer, and the photos and videos are recovered from that image — either by repairing the file system or by carving files out by their type, which finds images and clips even when the index is gone. There’s one bit of good news that SSDs don’t enjoy: cards don’t use TRIM, so even deleted photos are often recoverable.
Video needs a little extra care — a large clip interrupted mid-write can lose the small piece of data that tells a player how to read it, which can be rebuilt separately. But stills, in particular, come back well from corrupted cards.
Sometimes the fault isn’t the file system but the card itself — snapped, bent, water-damaged, or a dead controller so it isn’t detected at all. This is harder, because modern cards are usually monolithic: the controller and memory are moulded into a single solid block, with no separate chip to lift off. Recovery means locating the card’s internal test points and reading the memory directly, which is specialist work and not always possible.
If a card is physically broken or completely undetected, don’t bend or force it — that can finish off a fragile connection. It’s a case for a lab rather than home software.
Keep it simple: stop using the card, don’t format it, and don’t save new photos to it. If it’s a logical fault and you’re comfortable, reputable recovery software run in read-only mode can retrieve the photos; if it’s physically damaged, undetected, or the data is irreplaceable, a lab is the safer route.
Either way, the earlier you stop using the card, the better the result. And going forward, offload photos regularly rather than leaving months of memories on a single small card — they’re easy to lose and easy to back up.
What people ask us most about corrupted memory cards.
Usually not. That message means the file system is corrupt, not that your photos are gone — they’re typically still in the card’s memory. The essential thing is to decline the format, because formatting removes the records needed to recover them. Take the card out, stop shooting to it, and recover it read-only; the photos usually come back.
Often yes — more reliably than from an SSD. Memory cards don’t use TRIM, so deleted photos usually remain in the memory until they’re overwritten by new ones. The key is to stop using the card the moment you realise, so nothing writes over the deleted files, then recover them by their file type.
Sometimes, but it’s harder. Most modern cards are a single moulded block, so recovery means reading the memory directly through the card’s internal test points — specialist work that isn’t always possible. Don’t bend or force a broken card, as that can damage a fragile connection further; a lab assessment will tell you what can be done.
A card that asks to be formatted usually still has your photos on it. Send it in for a free diagnostic and we’ll recover what’s there. Post it in from anywhere in the UK, or drop it to us in Belfast.