How to Solve '- 60 bad master directory block' Error?

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A HFS (Hierarchical File System) volume comprises of five main structures: Boot Blocks, MDB (Master Directory Block), Volume Bitmap, Extent Overflow File, and Catalog File. Out of these structures, MDB is the one that defines data itself. Located at logical block 2 of the volume, MDB is an important structure that consists of valuable information that is used to locate data on a disk. A damaged directory is a direct indication of data loss. As such, a condition with no data backup can leave in an unavoidable situation of using a Macintosh data recovery utility.

A corrupted MDB is mostly a result of unexpected power outage. To clarify the related problems, consider yourself as a Mac OS X user who experiences a power failure on his Mac OS X computer. Next time, when you try to start your computer, a gray screen greets you. You also receive an error message that reads:


“-60 bad master directory block”


While preventing your access to the data, this error won't allow you to boot Mac OS X computer further.


As the error message mentions, this is a case of MDB corruption. Apart from power outage, virus infection can also lead to MDB damage.


Steps to Recover

Below mentioned steps help you recover such damaged disks in case of MDB corruption:


* If you have a valid and good data backup, clean the disk and simply restore the data.


* In the absence of a backup, you can repair the damaged directory by 'Repair Disk' function of 'Disk Utility. For an unbootable computer, you need to boot from the installation disk or connect the disk in disk mode to another working Mac OS X computer.


* Sometimes, the damage can be too extensive, and 'Disk Utility' might take considerable amount of time or in worst cases, might fail completely. In case of complete failure, you should use a Data Recovery Mac application. A Mac Data Recovery software can scan a logically crashed Mac disk and retrieve maximum data in the safest manner.