Unmountable_Boot_Volume

El problema que tuve con una hp pavillon en 2002
When you use volumes that use the NTFS file system on integrated device electronics (IDE) drives with caching enabled, you may receive the following error message during startup:
Stop 0x000000ED
Unmountable_Boot_Volume
The normal recovery process in such a case is to run the chkdsk /r command from Recovery Console, and then continue. On OEM versions of Windows XP, the Recovery Console may not be accessible. If this fix has not been included in the OEM build of Windows XP, you may not be able to enter Recovery Console and run the chkdsk /r command for recovery. For additional information, click the article number below to view the article in the Microsoft Knowledge Base:

308402  Cannot Log On to Recovery Console After Running Sysprep in Windows XP

Because of the write-pattern optimization in IDE disk drives, the caching routines sometimes write data out of order to keep drive write speeds at the fastest possible level depending on where data is located on the disk. This opens a timing window where the NTFS disk system could have critical tables damaged if a write is not finished. Microsoft has recommended in the past that caching on IDE drives be turned off on programs with somewhat critical data that is stored on the disk or for situations that allow the slight drop in overall speed. Programs with critical data may need to use SCSI drives, which have better control of data transactions.
To resolve this problem, obtain the latest service pack for Windows XP. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

322389  How to Obtain the Latest Windows XP Service Pack

To resolve this problem, obtain the following update from the Microsoft Windows Update Web site:

Download the "Critical Update, February 10, 2002" update now

Release Date: February 10, 2002

Microsoft has confirmed that this is a problem in the Microsoft products that are listed below. This problem was first corrected in Windows XP Service Pack 1.

• Microsoft Windows XP Home Edition
• Microsoft Windows XP Professional