[Solved] Couldn’t Modify Partition Map SD Card

🕔 5 minutes read

The error "Couldn't modify partition map" can appear on an SD card due to several reasons, putting your SD card data at risk. This article will explain the causes, provide solutions, and guide you on how to recover your SD card data using Remo Recover.

Couldn’t modify partition map SD card -  People often encounter this error while formatting or reformatting their SD cards with Disk Utility on Mac machines. Usually, this problem occurs when the Mac system has done severe damage by corrupting the partition map of the SD card. Consequentially, people encounter data loss.

Disk Utility Error Map

Couldn’t modify partition map

"any thoughts on this? or is this the end, and my friend's best bet at this point is to send the drive out to an actual data recovery professional? lol."

Source: Reddit

To fix this issue and recover data lost after partition map corruption on SD card, we provide you with most the reliable solution to fix the issue and safeguard your files on the SD card. To know how to, continue reading...!

What is Partition Map?

Before going for the solution, let’s understand what basically a partition map is. A partition map is a unique layout of any storage device that contains vital information about each Volume/partition.  It contains the source files that were used to create a partition, the function, and the global data which is included in a partition, etc.

Why does Partition Map get Corrupted?

The most frequent reason behind the corruption of the partition map is severe virus attacks, formatting, etc. If the boot sector of the storage device gets damaged as a consequence of improper system shutdown, sudden power surge, etc., then the SD card will not be mounted with read and write mode, resulting in data loss. In such an instance, your SD card becomes unreadable.

Note: Do you know why an SD card shows less storage size than the actual one? If you have encountered such issues, then check out this article to restore SD Card to full capacity

Solutions to Fix “Couldn’t Modify Partition Map SD Card Error:

Since Disk Utility cannot repair a damaged partition map, you can only format the SD card to fix the corrupt partition map. However, to avoid data loss, data recovery from SD cards should be your first priority. So, utilize Remo Recover, a trusted data recovery tool to perform corrupted SD card recovery on Mac before fixing the error.

Solution #1 - Recover Data Lost after Partition Map Damage with Remo Recover Tool:

Remo Recover software allows you to recover data lost or deleted from your SD card on Mac in just a few simple steps. In fact, it is capable of recovering files from formatted, unreadable, unmountable, and inaccessible SD cards too with utmost ease. The tool is compatible with macOS Catalina, Mojave, High Sierra, Sierra, and previous versions

Guidelines to recover lost data after corrupt partition map:

Step 1: Download, and install the free version of Remo Recover Software on your Mac system. After successful installation of the software, launch it. From the main screen, select “Recover Volumes/Drives” option.

Remo Recover Mac Main Screen

Step 2: Next, select “Volume Recovery” option as shown in Fig. 2

Remo Recover Volumes Recovery

Step 3: Now, choose the SD card drive from where you have to recover files, and click “Next” to continue, as illustrated in Fig 3.

Remo Recover Mac Select Volume

Step 4: Now, the software scans the selected SD Card drive. After the completion of the scanning & recovery process, a list of recovered files from the SD card is displayed in File Type View.

Remo Recover Mac Recovered Data

Step 5: At last, click the “Save Recovery Session” option to save the entire recovery process, and if you are satisfied with the tool, then activate the license key and save the recovered files without re-scanning the SD card again. The “Open Recovery Session” option helps you to continue the recovery process at the point where you left the recovery process.

Remo Recover Mac Save Recovery Session

Once you have successfully recovered all your data lost after partition map corruption, go ahead with a solution given below to fix damaged SD card partition map.

Solution #2 - Fixing “Couldn’t modify partition map SD card” error using Disk Utility:

Step 1: If the SD card is not completely damaged/corrupt, then the solution for this problem is to create a new partition map on the SD card. This is possible with the Disk Utility using the hidden option Show All Devices

Disk Utility All Devices

Step 2: Now, you will be able to select the device (SD Card). Here, make sure that you select the SD card and not the partition. Just right-click and click on Erase option

Disk Utility Erase Disk


Step 3: Once you click on Erase option, you will see a screen as shown in the figure below, and you will be able to use your SD card again.

Disk Utility Erase Disk Success

Solution #3 – Fixing “Couldn’t Modify Partition Map SD Card” Via Command Line

diskutil list

My SD Card is /dev/disk2, and the following is the command to erase the SD card partition:

diskutil eraseDisk ExFAT USBNAME /dev/disk2


Here, we have explained why the SD card partition map gets corrupt and provided free solutions on how to fix the “Couldn’t modify partition map SD card” error on your Mac machine. The recommended way would be to recover data from an SD card before you try out these troubleshooting tips. We hope it helped you in resolving the issues with your SD card.

Make sure that you have a regular backup of the files on the SD card to avoid data loss problems on any occasion of SD card corruption.

Frequently Asked Questions

Why am I unable to modify the partition map on my SD card?

If you are unable to modify the partition map on the SD card then the issue could be:
- Check if the SD card is locked
- File system errors.
- Damaged hardware.

How to recover data from an SD card with a "Couldn't modify partition map" error?

To recover data from an SD card with a "Couldn't modify partition map" error, you can download and install Remo Recover and scan the SD card.

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John Harris

With a decade of experience in data recovery, John Harris, Senior Editor at Remo Software, is your go-to specialist. His focus includes partition management, Windows solutions, and data troubleshooting, delivering insightful content that serves both users and search engines.

John's expertise shines through in illuminating blog posts, untangling data loss intricacies across diverse storage platforms. His mastery extends from file systems to SD cards, USBs, and external drives on Mac and Windows.

Recognized by cpomagazine, everythingusb, and more, John Harris is your trusted data recovery guide. You can also find his articles featured on correctblogger.com, computertechreviews.

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