simple question: where is the parallels version of hal.dll stored?

Ok, I'm having the notorious "hal.dll corrupt" message when trying to boot into parallels, using the bootcamp partition.

I can boot into bootcamp directly, without problem.

I have two different versions of hal.dll (one that is 140K, one that is 112K) from different places (the original bootcamp system32, and a parallels disk image system32).

My assumption is that the parallels file is broken somehow. So, I would like to try copying each of these over it, so that I can see if it will boot.

The question is: where are these files located, so I can look at them? Does anyone know?

thanks.