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How to Fix Damaged/Corrupted Partition Map Error in Disk Utility

Updated on Friday, June 14, 2024

iBoysoft author Anna Yuan

Written by

Anna Yuan
Professional tech editor

Approved by

Jessica Shee

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Summary: This post tells how to fix the damaged/corrupted partition map error. If you failed to repair your hard drive using First Aid and see this error in Disk Utility, you can use iBoysoft Mac Data Recovery to recover data from the disk first.

fixing damaged partition map

In Apple support communities, many people complained that they got the error message: Fixing damaged partition map when they tried to verify and repair an unreadable or unmountable drive in Disk Utility. Here's a real-life example:

This morning I plugged in the drive and got this message: "The disk you inserted was not readable by this computer." I tried Disk Utility First Aid and got this message: "Fixing damaged/corrupted partition map. The operation couldn't be completed. The operation failed..." I have backed up about two-thirds of the data on the drive but the remaining third has some irreplaceable data.

So in this post, we will talk about how to solve it when the "Fixing damaged/corrupted partition map" operation failed in Disk Utility.

Fixing damaged corrupted partition map error in Disk Utility

Why does the partition map get damaged?

The most frequent reason for a damaged partition map is bad sectors, especially the boot sector. If the boot sector gets corrupted as a consequence of improper system shutdown, sudden power surge, etc., the storage device will not be mounted with reading and write mode resulting in data loss.

How to solve the Fixing damaged partition map error?

Since Disk Utility can't repair the damaged partition map, you can only format the drive to replace the damaged partition map. But to avoid important data loss, you should perform data recovery at first.

Step 1: Recover lost data after partition map damage

iBoysoft Mac Data Recovery is able to recover lost data after partition map damage. It's capable of deleted file recovery, formatted data recovery, unreadable, unmountable, and inaccessible drive data recovery, deleted/lost partition data recovery, etc. It is compatible with macOS 12/11/10.15/10.14/10.13/10.12 and OS X 10.11/10.10/10.9/10.8/10.7 and works fine on M1, M1 Pro, and M1 Max Mac.

Tutorial to recover lost data after partition map damage with iBoysoft Data Recovery for Mac:

1. Free download and install iBoysoft Data Recovery for Mac on Mac.

2. Launch iBoysoft Data Recovery for Mac.

3. Select the drive whose partition map is damaged and click Search for Lost Data.
Recover lost data after partition map damage with iBoysoft Data Recovery for Mac  
4. Click Preview to preview the scanning results, choose the needed files and click Recover to get them back.
preview and recover data from Mac drive  
5. Have a check to ensure you have got all lost data back. Save the recovery results to an external hard drive to avoid data loss.

Step 2: Solve the Fixing damaged/corrupted partition map error by reformatting

  1. Launch Disk Utility from Utilities.
  2. Click the icon of the drive whose partition map is damaged on the left part of the window.
  3. Click on the Erase button at the top of the Disk Utility.
  4. Fill in the related information (name, format, scheme), then click Erase.

Other common partition map errors

Besides the "Fixing damaged/corrupted partition map" error, you may face the other partition map errors someday, such as the "Couldn't modify partition map" error and the "Problems found with partition map which might prevent booting" error. Why do these partition map errors occur on your disk?

Couldnt modify partition map

Bad sectors, especially the boot sector should be responsible for the partition map error. Luckily, to fix these two errors on Mac, you can still use the above-mentioned solution.


Tips to prevent your partition from damages

If you don't want to perform partition map repair again, here are plenty of things you can do to avoid the partition map from damage:

  • Since computer virus is the most common reason behind partition damages, make it a habit to always scan your external devices. This is especially true if you use your external devices on various computers as they are more vulnerable this way.
  • Do not install any software that is pirated by illegal operators, install software from trusted sources instead. This will not cause any irreparable damage to your partitions. Depending on the severity of the damages, partition repairs can cost more than buying unauthorized software.
  • Try to avoid performing sudden force shutdown on Mac as this may cause damage to the disk.