When a camera does not recognize an SD card, the cause is usually a poor connection, a locked card, an incompatible format or a damaged card. Work from the simplest fix to the most drastic one, and copy your photos off the card before you format it. Formatting erases the contents, so use it as a last step.
Common Causes
- A card that is not fully seated or has dirty contacts.
- The lock switch on the side of the card is in the locked position.
- The card was formatted in another device or computer with a file system the camera does not read.
- The card type or capacity is not supported by the camera.
- Corrupted files, often after removing the card while writing.
- A worn or damaged card.
Step by Step: Troubleshooting
- Turn off the camera. Always power down before removing or inserting a card.
- Reseat the card. Take it out, check that it is the right way around, and push it in until it clicks.
- Check the lock switch. Slide it to the unlocked position.
- Clean the contacts. Wipe the gold contacts on the card gently with a dry, soft cloth, and look into the card slot for dust or bent pins.
- Try another card. If a second card works, the problem is probably with the first card. If neither works, suspect the camera.
- Test the card elsewhere. Insert it in a computer or card reader. If it opens, copy all photos to your computer right away.
- Update the camera. Check the maker page for a software update and for the list of supported card types and sizes.
- Format in the camera. Use the format option in the camera menu, not the computer. This sets up the card with the structure your camera expects.
- Try recovery software. If the card holds files you need and will not open, a recovery tool may retrieve them. Stop using the card first.
Prevention Habits
- Format new cards in the camera before first use.
- Never remove the card while the access light is on.
- Do not let the battery run out while shooting.
- Copy photos to a computer soon after a shoot and keep a second copy.
- Replace cards that have shown repeated errors.
- Store cards in a case, away from moisture and dust.
FAQ
Will formatting fix every error?
Formatting resolves many file system problems, but not a physically damaged card or a card the camera cannot support. If errors return after formatting, replace the card.
Why does the card work in my computer but not my camera?
The camera may need to set up the card itself, or the card may be a type or size the camera does not support. Format it in the camera after saving your files, and check the supported list from the maker.
The Short Version
Reseat the card, unlock it, clean the contacts and try another card. Save your photos before formatting in the camera, and replace cards that keep failing.
