How to repair corrupt SD card in Android?

A corrupt SD card can be very frustrating for Android users. Important photos, videos, and other files stored on the SD card can become inaccessible if it becomes corrupt. Fortunately, there are several methods users can try to repair and recover data from a corrupt SD card.

What Causes an SD Card to Become Corrupt?

There are a few common causes of SD card corruption on Android devices:

  • Improperly removing the SD card without unmounting it first
  • A sudden power outage while files are being written to the SD card
  • Physical damage to the SD card
  • Formatting errors or interruption of the formatting process
  • Malware or viruses infecting the SD card
  • Too many read/write cycles causing the card to wear out

Corruption can affect either the file system of the SD card or the individual files stored on it. The file system corruption prevents the device from being able to properly read the card at all. Individual file corruption may allow the card to be read but certain files are damaged and inaccessible.

Step 1: Remove the Corrupt SD Card from the Device

The first step is to safely remove the corrupt SD card from the Android device. This prevents any further damage being done to the files on the card while troubleshooting the issue. Here is how to properly remove an SD card:

  1. Open the Notification panel and tap the “Eject” button next to the SD card name. This unmounts the card from the system.
  2. Alternatively, go to Settings > Storage and tap the “Unmount” button next to the SD card name.
  3. Remove the SD card from the device.

It is important to never remove an SD card without unmounting it first. This can lead to more serious corruption issues.

Step 2: Insert the Card into a Computer

With the corrupt card removed, the next step is to insert it into a computer’s SD card reader. This allows you to run data recovery software to scan and repair the card.

If the computer does not have a built-in SD card slot, you will need an external USB card reader. Make sure it can support the full capacity of your SD card.

With the card inserted, the computer should recognize it as an external drive. If the computer cannot detect the SD card, the file system corruption is likely very severe.

Step 3: Try the CHKDSK Utility

If using a Windows PC, the built-in CHKDSK utility can scan and repair certain SD card errors. Here is how to use CHKDSK:

  1. Open File Explorer and right-click on the connected SD card drive.
  2. Select “Properties” then open the “Tools” tab.
  3. Click “Check” under the Error Checking section.
  4. Check both boxes: “Automatically fix file system errors” and “Scan for and attempt recovery of bad sectors”.
  5. Click “Start” to begin scanning the drive.
  6. Allow CHKDSK to finish the scan. This may take some time depending on the card size.

After CHKDSK finishes, check if the card corruption is fixed by examining files and folders. If the problem persists, you will need 3rd party recovery software.

Step 4: Run Data Recovery Software

If CHKDSK is unable to repair the corruption, the next step is to use proper data recovery software. These programs are designed specifically for retrieving data from damaged drives and cards.

Some of the top SD card recovery tools include:

Software Key Features
Disk Drill Free recovery up to 500MB. Scans and repairs SD cards. Easy to use interface.
Recuva Free to use. Advanced deep scanning modes. Recovers images, video, documents.
Photorec Open source tool. Very robust RAW file recovery.
R-Studio Powerful recovery algorithms. Rebuild damaged partitions.

The general process for using data recovery software is:

  1. Download and install the software on your computer.
  2. Run the program and select the SD card drive as the location to scan.
  3. Select a deep scan or thorough scan option (this takes more time but finds more files).
  4. Wait for the scan to complete.
  5. Preview found files and select those you want to recover.
  6. Choose a folder to save the recovered data.

Advanced tools like R-Studio may also be able to rebuild damaged partitions and fix boot records on more seriously corrupted cards.

Step 5: Low-Level Format the Card

If data recovery software is unable to fully repair the SD card corruption, the next step is to low-level format the card. This completely erases and recreates the file system.

Warning: This will erase all data on the card. Only perform a low-level format if recovery failed.

To low-level format, either use the tool included with your memory card brand, or use free software like SDFormatter. The steps are:

  1. Download and install the low-level format tool.
  2. Insert the SD card into the computer.
  3. Run the format tool and select the card drive.
  4. Choose “Low-level format” and start the process.
  5. Wait for the format to fully complete.

This should fully reformat the card and repair any file system issues. You can now attempt to recover any lost files again after the format using data recovery tools.

Step 6: Check for Physical Damage

If low-level formatting does not fix the corruption, the SD card itself is likely physically damaged. Try the following checks:

  • Inspect the SD card for any visible damage or broken pieces.
  • Check the metal contacts for dirt, corrosion, or scratches. Clean with isopropyl alcohol if needed.
  • Try inserting the card into a different device like a phone, camera, or second computer.
  • Check if the manufacturer’s logo is visible and legible on the card.

If the card itself seems physically damaged, the only option left is to replace it with a new SD card. The data may be irrecoverable if there is physical degradation.

Tips to Avoid SD Card Corruption

Following certain best practices can help prevent SD card corruption from happening in the first place:

  • Always unmount the SD card before removing it from any device.
  • Be gentle and careful when handling the card.
  • Don’t store important files exclusively on the SD card. Also save them to internal device storage or cloud backups.
  • Open the phone’s SD card tray carefully to avoid damaging the card.
  • Regularly backup files from the SD card to a computer or cloud storage.
  • Don’t use very low quality, counterfeit cards that are more prone to failure.

Recovering Data from a Corrupt SD Card

With physical damage ruled out, software recovery tools offer the best chance of restoring lost files from a corrupt SD card in Android. The exact technique depends on the type of corruption:

File System Corruption

If the entire file system is corrupted, recovery software can often still extract RAW file data. This ignores the file system damage. The folder structure may be lost but the files can be retrieved.

Individual File Corruption

Corrupt individual files can sometimes be repaired. Advanced data recovery tools utilize different scanning algorithms to locate file headers and rebuild damaged parts. Files may be partially recovered.

Recovering Photos

Since photos are so important to users, some recovery tools like Disk Drill have specialized functions just for recovering image and video files. This reconstructs the complex media formats.

With powerful scan modes and reconstruction algorithms, recovery software provides the best chance to get back lost files from a corrupt SD card. Follow the proper steps to maximize your chances.

Conclusion

While SD card corruption can make data inaccessible, there are several effective methods users can employ to attempt recovery:

  • Use CHKDSK or file recovery software to scan and repair the card.
  • Reformat the card if needed to fix file system issues.
  • Check for physical damage as a last resort.
  • Practice safe usage habits like proper ejecting to prevent corruption.

In many cases, recovery tools can restore lost photos, documents, and other important data from the damaged SD card. With the right process, users have a good chance of getting their files back and fixing the corruption.