Emergency · memory card reporting CRC read errors
SD card CRC error: preserve data before repair
What should I do about a cyclic redundancy check error on an SD card?
Short answer
First stop repeated copy attempts: a CRC error means Windows could not read data reliably, not that files were deleted. Try one other known card reader, never format the card and avoid endless rescans. If the error persists, the card disconnects or gets warm, a recovery lab should image it before any repair.
The situation
Windows stops reading with a CRC error message.
Treat a CRC error as a reliable-reading problem first, not an invitation to format the card. A filename may remain visible while part of its content cannot be read. Switching recovery scanners does not automatically remove the read error. Preserve what remains without running endless retries against the same source.
01 / Diagnose
Work out what actually disappeared
Record the full message, affected filename and whether failure always occurs at the same position. Check external connections with the source disconnected. If the card otherwise remains stable, one attempt with a known working reader may help isolate the path; stop if the error returns.
Windows describes ERROR_CRC as a data error during a cyclic redundancy check. The message does not establish deletion or identify the faulty component by itself. The connection between the card and computer is also part of the investigation.
Check the last known path, trash and backups without writing to the original device.
02 / Protect the source
Preserve the best recovery chance
- 1
Stop automatic copy retries and document the affected files and the error message already reported.
- 2
Do not use repair or formatting functions; disconnect a card that heats up or repeatedly drops its connection.
- 3
Have valuable or unstable media preserved with a suitable process that records unreadable regions and acquisition errors.
- 4
Continue examination on the resulting working copy and save extracted files onto additional healthy destination storage.
Do not immediately run CHKDSK repair options or a succession of full deep scans. Do not write test patterns to the card. Successfully copying a few small photographs does not establish that every part of the source has become reliably readable again.
03 / Choose the method
Match the tool to the source
For stable, readable exFAT, NTFS and FAT16/FAT32 or uncompressed IMG, DD, RAW and BIN images.
Unconfirmed exports are marked .UNVERIFIED.
File Recovery Hero requires a stable readable exFAT source or a supported raw image. It does not repair hardware or replace imaging designed for failing media. Once an appropriate preserved copy exists, its remaining media content can be examined within the supported scope.
04 / Verify
Check the recovered content, not just its name
Check acquisition logs for unreadable areas and keep incomplete exports separate. Open photographs completely and inspect the entire duration of video clips. Missing picture or sound sections mean that a result remains incomplete even when File Explorer reports a plausible file size.
Keep the source until two verified copies exist. One working preview is not enough.
Sources and technical references
FAQ
Questions about this recovery case
Can memory card reporting CRC read errors be recovered in this situation?+
Treat a CRC error as a reliable-reading problem first, not an invitation to format the card. A filename may remain visible while part of its content cannot be read. Switching recovery scanners does not automatically remove the read error. Preserve what remains without running endless retries against the same source. The result still depends on what remains readable on the source.
What should I avoid before scanning?+
Do not immediately run CHKDSK repair options or a succession of full deep scans.
Does scanning write to my memory card?+
Your memory card is only read. Nothing is saved to it.
How do I know whether the result is complete?+
Check acquisition logs for unreadable areas and keep incomplete exports separate.
Preserve what remains.
Check the source first, then choose the appropriate next step.
Scan for free first, then decide.