Unmountable Boot Volume in Windows

An unmountable boot volume error indicates a problem booting from your hard drive

If you receive an "unmountable boot volume" error when trying to start up your Windows computer, you will need to investigate several possible causes. The simpler causes can usually be easily fixed.

Background

The unmountable boot volume error means that Windows is unable to read the filesystem on your hard disk drive. This could indicate that your drive failed. It can also indicate a loose or incorrect drive cable, an incorrect setting in your system BIOS (basic input/output system,) or a software problem.

Resolution

It's important to check that a PC does not have an external hard drive or USB storage device connected. The PC may be attempting to boot the computer with it. It is also important to check the hard drive cables and check the system BIOS does not have a "fast UDMA mode" setting enabled. A computer can also be booted using the Windows setup disk. The Startup Repair function on Windows Vista and Windows 7 can help to resolve the problem.

Warning

Certain methods used to recover from an "unmountable boot volume" error could cause data loss if performed incorrectly. Make sure you familiarize yourself with the procedures for startup repair or recovery console from the instructions Microsoft provides online.

References

• Microsoft: Unmountable Boot Volume
• Microsoft: Startup Repair: frequently asked questions
• Microsoft: Startup repair