About Invalid Volume Header
The HFS Plus File System on your boot drive is consisted from the special types of files. They are the allocation file, the attributes file, the catalog file, the extents overflow file, the startup file, unused space, and user file forks. The Volume Header locates at the almost top of the structure as the core-- equivalent to the Master Directory Block for the legacy HFS volume format. A volume is files that contain information about the volume such as the date and time of the volume's creation and the number of files on the volume, as well as the location of the other structures on the volume to work systematically with the structural behavior.
There are two different meanings of the error message "Invalid Volume Header." One is
here, reported as a benign reaction on different versions of Mac OS X. Another is oppositely a filesystem error that you cannot access files and folders.
Troubleshooting
1. Preform the File System Consistency checK by
"fsck -fy" after starting up in a Single user mode. However, this will not solve the issue if the journal information block in the volume header has been corrupted. If this option does not help, chose step 2 or 3.
2. Purchase DiskWarrior 4.0 disc or greater. This is a very helpful utility to fix not only incorrect volume header information but many kinds of logical errors on the HFS Plus formatted volume for Mac OS X.
3. Perform "Erase and Install".
FYI: The standard longevity of hard disk drive is roughly 3 years in using 8 hours per day.
