One day last week, I completed my work at the office and told my Windows XP notebook to hibernate, as I do at the end of every work day. Rather than hibernating, the notebook sat idle while displaying the "Preparing to hibernate" message. I gave the laptop about 10 minutes to complete the hibernation process (the laptop usually takes about 2 minutes to hibernate and shut down), and when the process didn't complete, I pulled the plug on the system.
I rebooted the system so that I could check the hibernation properties for any clues about what might have caused this problem. The computer churned for a while, displayed the "Loading Windows XP" screen, and then crashed, giving me an "UNMOUNTABLE_BOOT_VOLUME" error message. I didn't panic; I just rebooted into safe mode.
Watching the system boot in safe mode let me observe the boot process as it loaded the necessary files to make XP run. All the files loaded, then the computer crashed again with the same "UNMOUNTABLE_BOOT_VOLUME" error message.
A search of Microsoft's Web site returned a link to the support article "'STOP 0x000000ED UNMOUNTABLE_BOOT_VOLUME' Error Message During Windows XP Upgrade". The article attributed this error to either a cabling problem or (in my case) an NTFS problem.
I booted the laptop with the XP CD-ROM, launched the Recovery Console, and ran Chkdsk /r (repair) on the boot drive. The repair operation took 45 minutes (on my 32GB hard disk with 20GB free), and my notebook booted successfully with no apparent data loss.
So, why am I telling you all this? My reason for sharing this story isn't to inform you about the problem (which turned out to be simple to fix), but to comment about a statement near the end of the Microsoft article: "This behavior is by design." If Microsoft recognizes the problem, why doesn't the company automate the fix, or at least provide an error message that includes information about the problem or fix? The average user will see the cryptic "STOP 0x000000ED UNMOUNTABLE_BOOT_VOLUME" message and panic. I realize that not every system problem has an easy answer, but when the problem is a recognized error with a simple solution, the OS should present the solution to the user, not hide it online.