Techopedia Explains Volume Boot Record (VBR)
An example of the volume boot record is the original DOS boot sector. Creation of a volume boot record happens when formatting of a partition occurs, and this would reside on the very first sector found on the partition. Volume boot records have two components: the disk parameter block and the volume boot code. The code contained in the volume boot record is operating-system specific. The code can be only invoked by either the machine’s firmware or by the code found in the boot manager or the master boot record.
If the code is invoked by the boot manager, then the process is known as chain loading. The volume boot record in certain file systems like FAT12 or FAT32 would also contain the BIOS parameter block, which provides the specific details and structures of the on-disk data structures used in the file system.
In case of corruption or incorrect configuration, volume boot record can be repaired by creating a new copy of the necessary code to the appropriate partition. The procedure for writing the new code will depend on the version of Windows in use.