A Mac OS X user installs security updates to protect his/her machine from all kinds of security threats, like viruses and malware. These security updates can be downloaded from the Internet. While these updates enhance the security of Mac OS X system, there are few cases when the system might crash during the installation of a security update. The two main reasons responsible for system crash could be boot sector corruption or catalog file damage.

In such situations, you encounter a folder icon at the time of booting of Mac OS X, rendering to inaccessibility of the data saved in Mac hard drive. To overcome such situations, you can use an inbuilt repair utility named ‘Disk Utility’. However, if the repair utility also fails to repair, then you will need to restore the data from an updated backup. But in the absence of an updated backup, you will need to search for a commercial Mac Data Recovery application to recover your data.

To practically explain the above situation, consider a real-time scenario wherein you are downloading a security update 2007-2004 on your Mac OS X 10.3.9 machine and your system crashes in between. Now when you reboot your system, you encounter a ‘broken folder’ icon. Furthermore, when you use ‘disk utility’ to resolve the startup issue, you encounter the below error message:

“Invalid B-tree node size.

Volume check failed.

Error: The underlying task reported failure on exit. (-9972)”

The above error message appears when the repair utility fails to resolve the startup problem. After the above error message appears, your Mac OS X 10.3.9 system becomes unbootable and all the files/folders saved in its hard drive become inaccessible.

Resolution:

The above error message can be resolved by following below mentioned steps:

1. Use ‘FSCK’ utility to overcome all disk corruption situations.

2. In case the error message continues to appear, reinstall Mac OS X using ‘Erase and Install’ method. After re-installation, restore all the files and folders from an updated backup. However, in case no backup is available, use a third-party Mac Data Recovery application.

Such Mac File Recovery tools use effective scanning techniques to scan and recover all lost files. These recovery utilities are safe and easy-to-understand.

Stellar Phoenix Macintosh Data Recovery provides absolute recovery of lost data from HFS, HFS+, HFSX, HFS Wrapper, and FAT file systems volumes. The user-friendly Mac File Recovery tool can be installed on Mac OS X 10.3.9, 10.4 Tiger, 10.5 Leopard, and 10.6 Snow Leopard.