Every OS faces some kind of problems that make it unusable, no matter how stable and powerful the operating system is. Even the most reliable OS Mac OS X can face problems that can lead to data loss. In order to handle such situations, to prevent data loss, and needs of Macintosh data recovery software; Mac includes Disk Utility application.
Though Disk Utility is a powerful utility that is capable of handling a number of issues with Mac OS X hard drive, however, there is no guarantee that it will work in all cases of system failure. There are some situations where Disk Utility may fail with the following error-
"The underlying task reported failure"
Subsequent to the above error message, when you check the Disk Utility log, it shows "-9972" error code. The error code - 9972 signifies that the volume's disk structure is damaged and cannot be verified/fixed by the tool.
Cause
The above error occurs due to severe corruption to the disk structure or the file system. Corruption can occur due to various reasons, such as virus infection, improper system shutdown, user error, and disk data structure damage. Disk Utility cannot handle serious damage and you need to use other Tools to repair mac volume and fix the issue.
Solution
Try out the below methods to sort out this behavior-
Use fsck command through Terminal to repair mac volume. You must run the fsck command in single user mode. Alternatively you can also start the command from a different hard drive volume.
Use third-party system utility to repair your Mac OS X hard drive. You are highly recommended to create a complete backup of your significant data to prevent data loss and need of Mac data recovery due to any conflict.
If none of the above methods work, you will have to perform 'Erase and Install' installation of Mac OSX OS Although, it resolves the issue, but also deletes all the data from hard drive.
To perform data recovery Mac in such cases, Mac file recovery software are required. The file recovery Mac software uses advanced HFS recovery algorithms to effectively recover Mac data.
HFS+ recovery software lets you recover Mac files on your own, as of their highly-interactive user interface. Mac data recovery software preserves absolute integrity of your data with read-only conduct.
