there are a number of posts trying to solve the problem
where the Windows firewall doesn't open
Message is
"Due to an unidentified problem, Windows cannot display Windows
Firewall Settings "

A symptom of the problem is that MSINFO32 displays that it's service
pack 1, whereas in internet explorer, clicking help..about, it
displays that it is service pack 2.

A likely cause is an experiment I did. Using a Win XP sp1 CD, I tried
repairing Win XP sp2.

I solved the problem by [re]installing service pack 2 from the
microsoft website. note-I didn't try uninstalling sp2 beforehand.