Camera will not read the memory card, or reports it as full or unwritable

Affects Ricoh GR III, Ricoh GR IIIx, Ricoh GR IV · 32 owner posts, 172 comments · 8 app-review mentions

What causes it

• Wrong card format entirely — the GR IV takes microSD while the GR III and GR IIIx take full-size SD.
• Card formatted by a computer rather than in the camera.
• Genuine card failure, or a worn card slot on heavily used bodies.

What to try, in order

Nothing here can damage the camera.

1. Confirm you have the right physical card type for your body before anything else.
2. Format the card in the camera, not on a computer. This resolves most cases and erases the card.
3. Try a second known-good card to separate a card fault from a camera fault.
4. All current GR bodies are UHS-I; a UHS-II card gains nothing and is not a fix.

How confident are we?

Assembled from owner reports. Ricoh has published no cause for this one.

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