Looking for Help with a My Documents Problem

I have a computer problem that has been giving me fits. I hope that someone here can help me with this.

I have a computer in which the power supply and part of the motherboard got fried. I would guess the problem origianated in the power supply and then killed part of the motherboard. Anyway, I pull the hard drive, pop it in an external case and fire it up. It appears to be working fine. I can access everything on the drive EXCEPT for the stuff in the My Documents folder.

For reasons that I won’t go into, we need to recover the files from this My Documents folder. (Please note, this is not my computer and it is not my fault that there is not a good backup). The drive appears to be working fine and every other file on the drive is intact and able to be retrieved. Does anyone have any ideas on what I can do to access the files within that folder?

Update: I guess I should have been a little more clear in my question. A commentor asked for clarification:

Are you going through C:\Documents and settings\[user]\My Documents?

Yes, this is how I am attempting to access the folder. I have also attempted to redefine this folder as the My Documents folder for the new computer.

Are you getting some kind of error?

Yes, I am being told that the folder is not accessible. This is the message I get anytime that I try to access the folder (even when I try to designate it as the My Documents folder for the new computer).