Windows Cannot Boot - 0xc0000225

I've had Windows 7 installed for months on my Thinkpad T60 laptop and today out of the blue when I tried to boot, it started the Windows loading screen and immediately I got this error: Status: 0xc0000225 Info: The boot selection failed because a required device is inaccessible.

Through some research, I see people get this problem when a repartitioning goes wrong or there's a problem with their dual boot. I'm not dual booting my machine and I haven't messed with my partitions since I installed the OS. This error is truly out of the blue.

I've run memory diagnostics from a Windows boot disc and hard drive diagnostics from my BIOS and neither found a problem. I don't have any backups to restore from so I'm hoping to find a fix for this. Anyone seen this kind of thing before?

Thanks

Edit: I really don't think the hard drive is dying. It's only 3 years old and has shown no problems so far. I am able to access the drive from an Ubuntu Live CD (thank god!) so I can backup my files if I need to format & reinstall the OS. But if I can access the drive fine, why can't I boot from it‽

SOLVED: I finally burned a new Windows 7 disc (legally) since I didn't have mine and the repair utility on it fixed the problem.

I would imagine that the hard drive is dying, the boot sector will be readable so Windows can get into the boot loader but no further.

I would remove the hard drive from the laptop and put it into another computer to retrieve data.

Alternatively, use the ThinkPad PC doctor to perform a full hardware test.