What Is a Boot Volume?

The boot volume is the disk partition that has an operating system installed. If your boot volume is not mountable, your operating system will not load.

Software Causes

If this just started happening without any hardware changes in the computer, your problem could be a corrupt file system. You will have to reformat your operating system partition to fix this problem, or use "chkdsk" in the command prompt of Windows (for detailed instructions, see "Unmountable Boot Volume" in the Reference section).

Hardware Causes

If you just installed the hard disk that the operating system is installed in and you plugged it in with a 40-wire ATAPI cable, try using an 80-wire cable instead. UDMA hard disks cannot use 40-wire cables.

Misconceptions

Your boot volume is not always your system volume. The system volume is the one that contains the files for your computer to detect which operating systems you are running. The boot volume contains the operating system itself. Both can coexist in the same drive.

Expert Insight

The reason why 40-wire cables cannot be used in UDMA hard disks is because sometimes instructions might be misinterpreted by the ATAPI interface in your motherboard.

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Unmountable Boot Volume

Definitions for System Volume and Boot Volume