What happens if a memory card becomes corrupt?

A corrupted memory card can be frustrating and lead to lost photos, videos, documents and other data. But what actually causes a memory card to become corrupted? And is it possible to recover data from a corrupted card?

What causes a memory card to become corrupted?

There are several potential causes of memory card corruption:

  • Physical damage – Dropping or bending the card can damage the flash memory chips or circuitry. This can make the data inaccessible.
  • Improper ejection – Not properly ejecting or unmounting the card from your computer/device can lead to corruption. Always use “Safely Remove Hardware” before removal.
  • Power interruption – Sudden power loss while writing data to the card can corrupt files. Always properly eject before powering off camera/computer.
  • Exceeding capacity – Saving data past the storage limit can overwrite control and directory data, corrupting the file structure.
  • Faulty card reader – Using a damaged or defective card reader could cause errors or corruption.
  • Viruses/malware – A virus or malware infection could modify or corrupt data on the card when connected to an infected device.
  • Format failure – An interrupted or incomplete formatting process can damage the file system, rendering data inaccessible.

What does memory card corruption look like?

Here are some common signs that a memory card has become corrupted:

  • Error messages – Your computer/camera may display errors like “Card cannot be read” or “Card blank or has unsupported file system.”
  • Unreadable files – You can see the files on the card but cannot open or access them.
  • Strange filenames – Filenames contain random characters or text.
  • File conversion issues – Programs encounter errors trying to convert RAW images or videos.
  • Freezing/crashing – Camera or computer freezes when trying to access the card.
  • Slow performance – Extremely slow write speeds and long lag times could indicate corruption.

Can you recover data from a corrupted memory card?

It is often possible to recover data from a corrupted memory card, but results vary based on the type and extent of the corruption. Here are some data recovery options:

  • Try the card in another device – Inserting the card into a different camera, computer or card reader may allow access if the issue is with the original device.
  • Card repair software – Specialized tools like CHKDSK (Windows) or First Aid (Mac) can detect and fix filesystem errors.
  • Data recovery software – Advanced recovery software can scan the card’s memory and rebuild corrupted data. Popular tools include Recuva, Disk Drill and Stellar Phoenix.
  • Send to a lab – For severe corruption, a data recovery lab can access the memory directly via hardware tools to extract data. High success rates but expensive.

The chances of success depend on the specific issue. Logical errors in the filesystem are most recoverable. However, physical damage to the card can make data irretrievable.

Best practices to avoid memory card corruption

You can minimize the chances of a corrupted memory card by following these tips:

  • Use reputable, high-quality cards – Avoid cheap or counterfeit cards that are less reliable.
  • Handle cards carefully – Don’t bend, drop, or expose cards to liquids, dust or high heat.
  • Eject properly – Always use “Safely Remove Hardware” before removing the card.
  • Don’t overfill – Leave 10-20% free space on the card to reduce overflow issues.
  • Format regularly – Perform low-level “full format” periodically to correct errors.
  • Backup data – Maintain backups on separate media in case the card fails.
  • Check frequently – Scan cards with CHKDSK or First Aid to find and fix problems early.

Following best practices reduces the chances of corruption. But it’s still possible for even new cards in perfect condition to fail spontaneously. That’s why vigilance and backups are essential.

What to do if your memory card becomes corrupted

If you encounter a corrupted memory card, follow these steps:

  1. Stop using the card – Continued use can overwrite your data making it harder to recover.
  2. Try the card in a different device – A different card reader or camera may be able to read it.
  3. Check for physical damage – Look for any external signs of damage or moisture.
  4. Scan with CHKDSK or First Aid – This can find and repair filesystem errors.
  5. Attempt data recovery – Use recovery software or a professional lab for best results.
  6. Low-level format – If data is recovered, full format the card to correct errors before further use.
  7. Discard or replace – Severely corrupted cards should be discarded to avoid damaging devices.

With an organized response, you have a very good chance of recovering your photos, videos and other data off a corrupted card.

Preventing Data Loss from Corrupted Memory Cards

Memory card corruption can happen unexpectedly, so it’s important to take steps to prevent data loss:

Use High Quality Cards

Invest in name brand memory cards from reputable manufacturers like SanDisk or Samsung. Avoid cheap, off-brand cards that are more prone to errors and failure.

Handle Cards Carefully

Be careful not to bend, flex, or drop memory cards. The internal components are fragile. Also avoid getting cards wet or exposing them to extreme heat which can lead to corruption.

Eject Cards Properly

Always eject the card properly through your computer or camera menu before removing it. Abruptly removing a card while data is being written can lead to file system damage or data loss.

Use Card Readers

A dedicated memory card reader can be less prone to corruption than using the card slot built into cameras and computers. The reader bears the brunt of repeated insertions instead of your device.

Avoid Exceeding Card Capacity

Don’t save data past the storage limit of your card. This can override the filesystem leading to irreparable corruption. Leave 10-20% free space.

Format Cards Regularly

Perform occasional full formatting of your cards to wipe them completely and correct any errors that may have developed over time with repeated use.

Make Backups

Diligently backup your memory card data to another device or the cloud. This provides protection in case the card becomes corrupted and data cannot be recovered.

Recovering Data from a Corrupted Memory Card

If your memory card does become corrupted, there are techniques you can try to recover the data:

Stop Using the Card

First, immediately discontinue using the corrupted card. Any further writes could overwrite your lost data making it unrecoverable.

Try the Card in Another Device

Insert the card into a different camera, computer or card reader. Sometimes the card slot itself is faulty, not the card.

Run CHKDSK or First Aid

These built-in utilities can detect and repair some kinds of filesystem errors and bring back lost files.

Use Data Recovery Software

Advanced software like Disk Drill scans the raw memory and reconstructs lost or corrupted data. This is highly effective for recovering photos, videos, and documents.

Send to a Data Recovery Lab

For severe physical memory corruption, specialized labs can repair cards and use forensic techniques to manually recover data at the hardware level.

Frequently Asked Questions

Why does my memory card keep getting corrupted?

Frequent memory card corruption is often caused by a faulty or low quality card that is prone to errors. It could also indicate an issue with the device’s card reader. Trying a high-end card from a reputable brand can improve stability.

Can you fix a corrupted SD card without losing data?

Yes, it’s sometimes possible to repair a corrupted SD card without losing data using file recovery software or tools like CHKDSK. However, severe physical damage may require a full format to correct, which erases all data.

Is it safe to keep using a corrupted memory card?

No, it is not recommended to continue using a card after corruption occurs. Ongoing use can further damage the card and overwrite data that could otherwise be recovered. It’s best to stop using the card and attempt data recovery.

What causes constant memory card corruption?

Frequent memory card corruption is typically caused by:

  • Low quality, defective cards prone to errors
  • A faulty memory card reader/writer
  • Failing to properly eject the card from devices
  • Power failures while writing data to the card
  • Exceeding the card’s storage capacity

How can you tell if a memory card is corrupted?

Signs of memory card corruption include:

  • Error messages when trying to access the card
  • Card not being detected or showing up as blank/raw
  • Unreadable files and folder structures
  • Garbage data or nonsensical filenames
  • Device freezing when card inserted
  • Very slow write speeds and performance

Can you do a hard reset on a SD card?

Yes, performing a full format or low-level format essentially does a hard reset of the SD card by reallocating sectors and clearing any corruption. This erases all data so should only be done after recovering files.


Memory card corruption can happen unexpectedly but is often repairable with the right tools and techniques. Investing in high quality cards, handling them with care, and taking precautions like safely ejecting and making backups can help minimize the risks. Periodically formatting cards can also help clear up errors before they become catastrophic. In the event your card does become corrupted, stop using it immediately and try data recovery software, hardware tools, and if needed, professional data recovery services. With an informed, planned response, you can usually recover lost files and photos and get back to creating memories.