I had this same problem. Like you, I discovered lots of info about it
online, but no real solution.
I ended up searching my computer for "proofing.en-us" and then pointing
the installer to that location.
I wrote up more detailed instructions he 'Solution: “Cannot
find Proofing.en-us” error when Installing Office 2007 |
RyanTAdams.com' (
http://tinyurl.com/6pg62r)