I am also getting the same error on a reinstall (due to a hard disk crash). I did the same reinstall about 1.5 years ago (not having great success with the hard disk

and that went fine - after install PCBS I installed the authoring system macros into MS-Word. I had been using the macros without a problem.
I am on Windows XP Pro SP3, which is what I was on for previous install. The only software I know that has changed is IE, which went from v. 6 to 8. And, the only other thing I know that has changed is the hard disk

I hope this information helps isolate the problem.