?Mac OS X operating system enables you to divide your hard drive into various volumes. Each volume can be used as a separate hard drive and any type of data can be stored on it. Every Mac system includes at least one system or boot volume that contains operating system. Each boot volume has a file system, such as HFS, to manage data. However, in some situations, Mac OS X operating system can not identify the volume and thus that volume can not be accessed. In such cases, you encounter severe data loss situations if an updated backup is not in place. At this point of time, Mac Recovery Software are required to get your valuable data back. In a practical scenario, you may come across the below error message when you try to access data from an HFS file system volume of Mac OS X hard drive: "-123 wrgVolTypErr Not an HFS volume [wrong volume type error or (obsolete) operation not supported for MFS]" After the above error message, HFS file system volume becomes completely inaccessible. To access your mission-critical data on the Mac hard drive volume, you need to find out the cause of this problem and fix it using File recovery mac . Root of the problem As stated in the above error message, this problem occurs when Mac OS X operating system can not recognize the format of HFS file system volume. It can be due to corruption of the HFS file system or HFS file system volume. Corruption is generally due to virus infection, improper system shutdown, and other such reasons. How to resolve this problem? In order to work around this problem, you should repair your hard drive using Disk Utility. It detects and fixes file system related errors. However, if the corruption is serious, you should format the hard drive and restore all your valuable data from backup. In case the backup is not updated or is corrupt, you have to opt for a third-party mac file recovery application. The software are specifically designed to carry out in-depth scan of the entire hard drive and extract lost, missing, and inaccessible data from it. You need not be technically savvy to use these tools for retrieving data as they have simple and interactive graphical user interface. The Mac Recovery utilities preserve absolute integrity of your valuable data with read-only demeanor. Stellar Phoenix Macintosh Data Recovery software recovers all lost, missing, and inaccessible data from corrupt or inaccessible Mac OS X hard drive volumes. The software is designed for Mac OS X 10.6 Snow Leopard, 10.5 Leopard, 10.4 Tiger, and 10.3.9 Panther. It recovers data from HFS, HFS+, HFSX, HFS Wrapper, and FAT file system volumes.