windows has encountered a problem communicating with a devide connected to your compu

[MPTech]

Trying to help a friend, don't have the specifics of his PC (it's a Thermaltake case, dual core with about 4gig of Ram, but I don't think that information is pertinant to the issue. I can find out if need be).
It is Win7 Ultimate 64-bit.

He's getting a message:

windows has encountered a problem communicating with a devide connected to your computer.

.......
File:\Boot\BCD

Status: 0xc00000e9

info: An unexpected I/O error has occurred

It will not boot normally or into Safe mode.

I removed the SATA HDD and connected it to another PC, via USB and looks like I can see and read all of the files on the drive. So the drive appears ok, from a mechanical perspective.

I installed a spare drive I had, and did a new install of Win7 Ultimate 64-bit and it installed fine and booted up.
So I don't think there's an issue with the PC or the connections and the DVD also works.

My guess is that Win7 was corrupted.

Can I re-install Win-7 (overlay?) without wiping out his current Documents? (I tried copying them to another drive, but it said I didn't have permission).
I'd like to repair his Win7, without wiping out his files and also so it doesn't have to be reconfigured and Drivers re-installed.

I've done this with XP in the past, but never tried Win7.

Any suggestions?
Am I on the right path?

Thanks!

[Steve R Jones]

You should always Google the error message

See "Method 2" in this:
http://social.technet.microsoft.com/...7-d8ba4b6cc54b