Hi Lighthouse & JD, thanks very much for both your efforts in getting this problem solved.
Actually, I have encountered this Windows Help/Support problem before, and it's the same geek website that helped me solve it, and too bad I lost that help link. Fortunately, I recall that it has something to do with the Dreamweaver 8 installed on Vista. And I got it fixed by installing a reg file "DW8_Fix_Help_and_Support", and it indeed help me solve that Windows Help/Support problem here.
Once again, thank you for ur time. Appreciate that!
Ash

