Recover Data after Apple Partition Map Corruption

“I have a 1TB Mac hard disk drive under Mac OS X 10.6 which seems to have a corrupt apple partition map. Actually what happened is, there was a sudden power failure while changing my Mac hard disk file system from HFS to HFS+, after which I was not able to access my Mac hard disk Volume. My friend said that interruption while conversion of file system often results in Apple Partition Map corruption; I’ve a lot of important data on Mac volume, can data from it be recoverable?”

Every Mac computer user may encounter corruption of Apple Partition Map at some point of time, where user loses access to important data. But luckily lost data from Mac hard drive after corruption of Apple Partition Map can be retrieved back with the help of effective data recovery utility. Before going into details of Mac data recovery, it is necessary to know what Apple Partition Map is.

What is Apple Partition Map?

Apple Partition Map is an advanced table partitioning scheme which is similar to MBR in Windows operating system. Apple Partition Map otherwise known as APM stores vital information’s such as number of Volumes on Mac hard disk, size of all Volumes, location of each hard disk Volumes and many other aspects. Hence damage of Apple Partition Map makes your Mac hard disk Volume data inaccessible. There are many possible reasons behind Apple Partition Map corruption and some of the prominent ones are discussed below:

  • Bad Sectors: APM gets corrupt mainly due to occurrence of bad sectors on Mac hard disk. You might know that hard drive consists of various sectors on which data is stored, bad sectors on hard drives is usually caused due to CPU over clocking, intense read-write operations, exposure to high temperatures/moisture, etc. If APM is located after bad sectors, then bad sectors won’t let OS to access the information stored on consecutive sectors and results in data loss
  • Boot Sector Corruption: If boot sector of a Mac hard disk drive can get affected as a consequence of improper system shutdown, sudden power surge etc. Hard Drive fails to boot operating system due to corruption of boot sector and Volume on Mac refuse to mount resulting in data loss

However you can try using “Disk Utility” application to fix issues with Apple Partition Map, but the success rate of this utility is very low. In such circumstances, the only option to access your Volume is by formatting it and recovering the formatted data using suitable data recovery application built for Mac system.

Mac Data Recovery Software:

Yodot Mac Data Recovery is an exceptional data recovery utility to retrieve data after Apple Partition Map corruption. This is a reliable recovery program to retrieve data from Mac volumes formatted with HFS, HFS+ and HFSX file systems. This software is also capable of restoring lost data from Mac system after Catalog Record corruption, Volume Header corruption, Journal File corruption and other critical data loss scenarios. Other than Mac hard drive, it can also restore data from external storage media namely external hard drives, memory cards, flash drives, iPods, etc.

Steps to get lost data from Mac after Apple Map Partition corruption:

  • Download and install the application to your Mac desktop / laptop
  • Open the installed application and follow the main screen steps
  • The software displays two option from the main screen
  • Select “Volume Recovery” or “Formatted / Reformatted Recovery” option based on your data loss scenario
  • The application now scans the whole computer and shows all logical, physical and external Volumes
  • Choose the Volume from where data is to be retrieved and simply click “Next” button
  • The software repeats the scanning process and displays all the deleted / lost data from the selected Volume
  • Choose the files and folders which you would like to recover back and click “Next”
  • At last, browse for the destination location to save your recovered files, but not to the same Volume from where data was recovered


  • Never use Mac hard disk that has bad sectors
  • Don’t use any third party utilities to repair your Apple Partition Map
  • Backup all your important Mac hard disk files before format operation

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