How do I format a corrupted micro SD card on my Android phone?

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How do I format a corrupted micro SD card on my Android phone

Quick Summary

Here are the key steps to format a corrupted microSD card on an Android phone:

  • First, try removing and reinserting the SD card to see if the phone recognizes it properly.
  • If that doesn’t work, connect the phone to a computer and try formatting the SD card using the computer’s SD card reader.
  • If the computer can’t format the card, try using SD Card Formatter software on the computer to overwrite the card and create a new FAT32 partition.
  • On the Android phone, go to Settings > Storage and tap the SD card name.
  • Tap the 3-dot menu icon in the top-right corner and select Settings.
  • Choose Format and confirm to erase all data on the SD card.
  • After formatting on the phone, the SD card should be usable again.

Try Removing and Reinserting the SD Card

As a first step whenever your Android phone is having trouble recognizing or working with an SD card, try the simple fix of removing and reinserting the card. Here’s how:

  1. Locate the SD card slot on your phone. It’s often on the side or bottom edge.
  2. Gently insert your fingernail into the slot and pop out the SD card.
  3. Inspect the contacts on the SD card for dirt, damage, or debris. Clean with a soft cloth if needed.
  4. Reinsert the SD card fully into the slot until it clicks into place.
  5. Open your phone’s Files app and see if the SD card appears properly.
  6. Try viewing photos and files on the SD card to see if the phone can access them.

Often a simple remove and reinsert is all that’s needed to get an unrecognized or corrupted SD card working again on Android. If the phone still can’t read the card however, move on to the next steps.

Try Formatting the SD Card Using a Computer

If your Android phone won’t recognize or interact properly with the SD card, try using a computer’s SD card reader to access and format the card instead. Here’s how:

  1. Use an SD card adapter or built-in SD card reader on a Windows PC or Mac to insert the card.
  2. See if the computer recognizes the card and can view files on it. If so, backup any needed files first.
  3. Go to the computer’s main Disk Management tool. On Windows, right-click the Start button and select Disk Management. On Mac, open Disk Utility.
  4. Locate the SD card in the disk list. You may see errors or that only some of the capacity is accessible.
  5. Right-click the SD card’s partition or volume and select Format or Erase. Choose FAT32 as the file system.
  6. Click OK to confirm formatting. This will erase all data on the card.
  7. Safely eject the SD card and reinsert it into your Android phone.
  8. Check to see if the phone recognizes it now and can store new files on it.

Formatting the SD card using the computer instead of the phone sometimes resolves issues the phone is having with reading it. FAT32 formatting is recommended for maximum compatibility.

Use SD Card Formatter Software

If your Windows PC or Mac cannot format the corrupted SD card, try using a free dedicated SD card formatting utility instead. Here are steps for using the popular SD Card Formatter app:

  1. Download and install the SD Card Formatter app for Windows or Mac from https://www.sdcard.org/downloads/formatter/
  2. Insert your SD card into your computer’s card reader.
  3. Open SD Card Formatter and select your SD card’s drive letter.
  4. Click the Format button to start formatting. Choose Quick format.
  5. Click OK to confirm formatting. This will completely erase and overwrite the card.
  6. Once formatting is complete, you can close the app and test the SD card in your Android phone.

The SD Card Formatter utility uses advanced formatting techniques designed specifically for SD cards. This can often resolve corruption issues when your computer is unable to format the card. Be sure to backup any needed files first.

Format the SD Card Using Your Android Phone

If you are unable to get the computer to recognize and format the corrupted SD card properly, you can try formatting it directly using your Android phone instead:

  1. On your Android phone, go to the Settings app.
  2. Tap Storage (or Storage & USB on some devices).
  3. Locate the listing for your SD card and tap it.
  4. Tap the 3-dot menu icon in the top-right corner.
  5. Select Settings from the menu.
  6. Tap Format and then tap Format SD card.
  7. Read the warning, then tap Format to confirm.
  8. The phone will format the SD card and erase all data on it.
  9. Once formatting is complete, the SD card should be usable in your phone again.

This process erases all data on the SD card and recreates the file system from scratch. If your phone can access the card at all, formatting it this way should resolve most corruption issues.

Tips When Formatting on Android

  • Move any data you need off the SD card first.
  • Try a Quick Format first, then Full format if issues persist.
  • Don’t interrupt the formatting process.
  • Double-check you are formatting the correct drive.
  • Restart your phone after formatting.

With the SD card empty, any errors or corruption in the file system can be fixed by your phone reformatting it completely. This gives you the best chance of resolving SD card problems.

Try a Different SD Card Reader

In some cases, the SD card itself is fine but there is an issue with the card reader or slot on your phone or computer preventing access. Try using a different card reader to see if that helps:

  • Try your phone’s SD card slot with another known good SD card.
  • Try your suspect SD card in another phone’s slot.
  • Try your phone’s card reader with different brands of card adapters.
  • Try inserting your SD card into multiple laptops’ card readers.

If your card only works in some readers but not others, the issue is with that device’s reader. If your card fails to work in multiple devices, the card itself is likely damaged.

Check for Physical Damage on the SD Card

Closely inspect the SD card itself for any signs of physical wear or damage. Look for:

  • Missing plastic pieces or cracked case
  • Bent or misaligned contacts
  • Scratches on the metal contacts
  • Corrosion or dust buildup on contacts

Even small defects in the SD card’s physical structure can prevent devices from reading it properly. If you see obvious damage, the card is defective and should be replaced.

Try Cleaning the SD Card’s Contacts

If the SD card has dirty or greasy residue on the metal contacts, try cleaning it off carefully with a soft cloth or eraser. Here’s how:

  1. Power off your phone and SD card when cleaning.
  2. Gently rub the SD card contacts with an eraser or microfiber cloth.
  3. Use a can of compressed air to blow away any detached particles.
  4. Check if contacts now appear clean and shiny. Repeat cleaning if needed.
  5. Insert SD card and power on phone. See if card is recognized properly.

Clean contacts allow for optimal connectivity. Be very gentle as the contacts scratch easily. Cleaning can resolve SD card issues caused by dirt buildup.

Test the SD Card Using H2testw

To check if your SD card has internal logical errors or defects, you can run a read/write test using free utilities like h2testw. Here is how:

  1. Download h2testw for Windows or F3 for Mac (free apps).
  2. Insert your SD card into your computer’s card reader.
  3. Launch h2testw and select your SD card’s drive letter. Click Write + Verify.
  4. The full card test writes files and checks read consistency.
  5. If errors are reported, you have a defective card that should be replaced.

Read/write testing checks for card defects that cause random data errors. This is a thorough way to determine if your SD card is faulty and the cause of corruption issues.

Low-Level Format a Failing SD Card

If your SD card is so corrupt that normal formatting fails, you may need to do a low-level format to completely wipe the card:

  1. On Windows, use a tool like SD Formatter or HDD Low Level Format Tool.
  2. On Mac, open Disk Utility and select Erase > Write Zeros.
  3. This overwrites all data by zeroing out the entire disk surface.
  4. Confirm you have selected the correct disk to avoid data loss.
  5. Low-level format rebuilds the file system and clears all previous errors.

This is a last resort option when SD cards will not format normally. It provides a deep clean by overwriting all data including corrupted system files. Back up needed data first.

Conclusion

With the right troubleshooting steps, you can often revive a corrupted SD card and continue using it in your Android phone:

  • Try reinserting the card and restarting the phone.
  • Format the card using your computer or phone’s built-in tools.
  • Inspect for physical damage and clean contacts.
  • Perform a read/write test to check for defects.
  • Repair the file system using low-level formatting if needed.

If cleaning and formatting your SD card fails to resolve the issues, the card is likely permanently damaged and needs to be replaced. Back up data regularly to avoid losing files if your card becomes corrupted.