Complete Guide to Fix Corrupted SD Cards & SD Card Data Recovery

By Katrina | Posted to Data Recovery, updated on Feb 19th, 2020 |

Summary: A complete guide to repair corrupted and unreadable SD cards. If your SD card won't work normally, here you will learn how to fix the corrupted SD card. To prevent data loss, you can also download free SD card data recovery software like iBoysoft Data Recovery to recover lost files.

SD cards are widely used in digital cameras, computers, and mobile phones. For instance, many Android phones use micro SD cards to expand storage capacity. However, the SD card will become inaccessible when it's corrupted. What's worse, such SD card corruption can even freeze your computer. But you don't even know why this SD card corruption. Moreover, mistaken solutions like formatting will cause further data loss on SD cards.

So, when confronted with such SD card failure, you should not let go of your important files and documents. Instead, you can find a fix in this article to repair corrupted, unreadable or damaged SD cards. At the same time, you can perform an SD card data recovery effectively.

Let's dive into details.

Table of contents
1. How does an SD card become corrupted?
2. How to fix when corrupted SD cards won't work on Windows 10/8/7?
3. How to recover lost data from corrupted SD cards?
4. How to avoid SD card corruption in future?

How does an SD card become corrupted?

Generally speaking, SD card corruption usually results from improper operation by human. So, you can recall that if you have done those wrong things to your SD card.

  • 1. Turning off the camera before the photos are completely written to your SD, SDHC, SDXC, or Compact Flash card. If you have done this, your photos on the SD card may be corrupted, or what's even worse, the whole folder would be empty.
  • Camera's SD card corrupted
  • 2. Removing the SD card when data transferring or photo edition is undergoing on computers. It's the same theory as the above one. The data would be in a buffer or cache sectors of your SD card, and you can't access it normally.
  • SD card data transfer interruption
  • 3. Frequently insert and pull out the same SD card on different cameras. Such operation causes damage to both the chip of the SD card and the Camera's card reader.
  • 4. Unsafely remove the hardware and eject the storage device. SD cards frequently get corrupted after abrupt removal. And you might get an error message on a Windows computer like 'drive is not accessible', 'you need to format the drive before you can use it', etc.

    SD card corruption caused by unsafe ejection

  • 5. Continually shooting and deleting images when the SD card is already full.
  • 6. Sudden interruptions while formatting SD cards, etc. In this case, if you check the SD card in Disk Management, you'll find its file system is RAW.

Those operations will corrupt your SD card and stop it working normally. Consequently, you can't write or even read your files on it. Then, is it possible to fix the corrupted/unreadable SD card without data loss? Definitely yes!

How to fix when corrupted SD cards won't work on Windows 10/8/7?

When an SD card becomes corrupted, all contents stored on it become unreadable. For example, you may find that your SD card is not showing pictures on the camera or computer. If you try to open the corrupted SD card on Windows computer, you will get some error messages such as 'File or directory is corrupted and unreadable' or 'The disk is not formatted. Do you want to format it now?' On a Mac computer, you may receive the error message "The disk you inserted was not readable by this computer.

Here is a user who experienced the same thing:

Hi All, we took tons of pictures on our personal point and shoot camera at my wedding. While taking the pictures, the immediate preview was available and there were never any error messages on the camera. However, none of our wedding pictures are available on the SD card anymore now. Are my photos gone forever? I've already tried Zero Assumption and it doesn't return any more pictures than what I can already see. Is there any other way I can fix this corrupted SD card and recover my pictures from this SD card?

-- From Tom's Hardware Forums

In this situation,, the first thing you should do is to stop using the corrupted SD card immediately. And you should not format it directly, as reformatting will wipe your data off the SD card. Fortunately, you can fix the SD card with these ready-to-use solutions.

Note: If you previously use the corrupted micro SD card on Android phones and it won't work now, you can take it out and connect it to a computer via a micro SD card adapter. With the solutions in this post, you can try to fix the micro SD card on the computer. And you don't need a special micro SD card repair tool for phones.

Solution 1:Try a different card reader or computer

Sometimes, the SD card is showing as unreadable (on Mac) or inaccessible (on Windows). It may not because the SD card is damaged. Instead, you need to check the connections. The computer won't detect the SD card if the card reader is not working, while a functioned card reader can be viewed in Device Management.

Check SD card reader in Device Management

You can insert another SD card to check if the slot on your computer is working. You can also try another card reader or even another computer. If your SD card can work on another card reader, then the SD card reader is the fault.

Solution 2:Check the corrupted SD card in Disk Management

When a Windows computer is not reading the SD card due to disk corruption, you can check and fix it in Disk Management. It's a system utility that you can view all disk information like the file system, partition, drive letter, and storage capacity.

Note: If you are using a Mac, you can try your luck with a similar utility called Disk Utility.

You may see three possibilities in Disk Management.

1. Windows can recognize the SD card's file system but show no drive letter

As you probably know, Windows needs to allocate a drive letter before you can access the files on a storage media. But if your computer fails to assign a drive letter to the SD card, you are not able to read this SD card. To solve this problem, you only need to assign a new drive letter to the SD card.

Step 1: Go to Disk Management.

Step 2: Find the SD card and check if you can see the drive letter.

Check drive letter of the SD card in Disk Management

Step 3: Check and click if the "Change Drive Letter and Paths..." option is available from the context menu.

Step 4: Click Add and follow the wizard to assign a new drive letter to this SD card.

Add drive letter to the SD card in Disk Management

If you can assign a new drive letter, the SD card would be readable then. But if you can't change or assign a drive letter because there is no list or option for this operation, you'd better recover data from this corrupted SD card to prevent data loss.

2. The SD card has a drive letter but the file system is RAW.

Probably, your SD card is formatted with FAT32 or exFAT file system, but now it showing up as RAW. A RAW file system means that the file system might be corrupted. And the operating system like Windows and macOS can't recognize it. Usually, you'll get error messages like "You need to format this disk before you can use it". In that case, you can also fix the RAW SD card using CHKDSK command or by converting RAW to NTFS/FAT32/exFAT as introduced later. But the safer option is that you can recover data from this SD card before you do any disk repair.

3. The information of the SD card is not showing up in Disk Management.

The worst thing is that you can't see the SD card's file system, partition information, and storage capacity at all. Then, the SD card either has too many bad sectors or is physically damaged. The computer will stop reading the SD card. You need to send it to a local data recovery service if you have important files on it. But usually, it would be costly.

Solution 3:Fix corrupted/unreadable SD cards with CHKDSK command

CHKDSK is a built-in Windows utility that can check the integrity of your disk and can fix various file system errors, such as bad sectors, lost clusters, cross-linked files, directory errors, etc. Therefore, you can try to fix corrupted SD card using command. If you successfully repair the SD card by CHKDSK command prompt, you will regain access to the SD card as well as to all your files.

Note: Mac has a similar command for disk repair. When the SD card won't work well on Mac, you can also run First Aid in Disk Utility.

Step 1: Plug your corrupted SD card into your computer with a card reader.

Step 2: Go to the Start menu of your Windows computer, type in "cmd" in the search bar, and press Enter.

Step 3: Right-click "cmd.exe" and choose "Run as administrator".

Step 4: Type in "chkdsk volume: /f" in the command prompt, where "volume" is the drive letter of your SD card. (For example, if the drive letter of your SD card is "G", then you need to type in "chkdsk G: /f".)

After several minutes, you will see "Windows has made corrections to the file system" in the command window. It means you have successfully fixed corrupted the SD card. And the SD card would not be unreadable if you access it.

Solution 4:Fix corrupted/unreadable SD card by reformatting

Chances are that CMD fails to fix the corrupted SD card, and the computer is not reading the SD card still. Or you received the error message "CHKDSK is not available for RAW drives" because your SD card has a RAW file system. In these cases, the file system of your SD card is severely damaged and CHKDSK command can't help.Thus, the only solution is to reformat the corrupted/unreadable SD card (By reformatting, the corrupted/unreadable SD card will be assigned a new file system and work again as good as new).

Warning: Reformatting will erase all data stored on the corrupted SD card, So, to prevent data loss, SD card data recovery is the first thing.

Step 1: Connect the corrupted and unreadable SD card to your Windows computer.

Step 2: Right-click on "This PC" or "My computer" on the desktop and choose Manage.

Step 3: Choose "Disk Management" in the left sidebar when you enter into "Computer Management".

Step 4: Locate your SD card by the disk information and right-click on it.

Step 5: Choose "Format" and then you can select the file system (Choose exFAT/FAT32 if you want to format it for Mac and PC), and set the cluster size in the wizard.

Step 6: Click "OK" to finish reformatting.

Solution 5: Check SD card warranty period

When your SD card is corrupted and unreadable, it is worth checking to see if the warranty of your corrupted and unreadable SD memory is still valid or not. If so, providing you don't have any important data stored on the SD card, it may be easier to simply seek a refund or replace the card with a brand-new one.

Solution 6: Contact the manufacturer's support team for help

If your corrupted SD card is not showing up on Mac or Windows Disk Management, it should be a hardware issue, please Contact the manufacturer's support team for help, whether you want a product replacement or repair service.

How to recover lost data from the corrupted/unreadable SD cards?

For most people, the data stored on the corrupted SD memory matters more than the card itself. So, many users are wondering how to fix corrupted SD card without formatting, i.e. without data loss. When you don't have a backup copy of the important files on the SD card, you can still recover lost data from the corrupted SD card with an SD card data recovery software.

Note: If you have already formatted the corrupted SD card, recovering data from the formatted SD card is also possible.

iBoysoft Data Recovery is a professional SD card data recovery software. It is particularly useful when dealing with SD card corruption because of its powerful data recovery ability. This data recovery software can recover data from different storage devices, including SD cards, memory sticks, micro SD cards, external hard drives, and USB flash drives. This data recovery software is fully compatible with Windows 10/8/7/Vista/XP and Windows Server 2019/2016/2012/2008/2003, where you can recover deleted/lost emails, photos, music, videos, audios, and other types of files with ease.

How to recover lost data from the corrupted/unreadable SD cards?

Infographic tutorial to recover lost data from the corrupted/unreadable SD cards

Recover lost data from corrupted/unreadable SD cards

Text tutorial to recover lost data from the corrupted/unreadable SD cards

Step 1: Download and install iBoysoft Data Recovery on your computer.

Step 2: Connect the corrupted/unreadable SD card to the computer with a card reader.

Step 3: Launch iBoysoft Data Recovery and select the corrupted/unreadable SD card in the interface.

Recover lost data from corrupted/unreadable SD card with iBoysoft Data Recovery

Step 4: Click "Next" to search for lost files on the corrupted/unreadable SD card.

Step 5: Double-click the found files to preview and then click "Recover" to get them back.

How to avoid SD card corruption in the future?

As SD cards are so frequently used in our daily life, it's worthy mentioning the tips to prevent SD card corruption again in the future. Here are some tips for SD card maintenance.

First, you should always eject an SD card on the computer by Safe Removal.

Second, use different SD cards on different devices.

Third, handle it gently.

If unfortunately your SD card got corrupted and there were important files on it, such as wedding photos, toddlers videos, work files, etc., you can follow the tutorial on this page to recover deleted/lost photos from SD cards with iBoysoft Data Recovery.

Finally, the most economical and fool-proof method to avoid data loss is to back up your files regularly.

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