First off, let me describe a few of my symptoms, Help and Support was not working(service was running), the extended tab in services.msc was blank, and I couldn't open up chm files. Chm files was the first hint I even had a problem cause my desktop was always able to view them, then I updated my xp sp2 to sp3 and was no longer able to view them. Tried every fix that dealt with the security flaw to no avail, and re-registering all the controls dealing with the display of chm files. Nothing seemed to work. So I figured maybe the service was somehow disabled/down. That's when I noticed that the extended tab was blank. The funny thing is they all showed up in the standard tab. Help and Support was not working from the start menu(you click on it got the hourglass and then nothing) and when I went to the security center to click on the help topics, it would come up and then close itself. So I read some posts that hinted at the fact that the Help and Support from the start menu messes up upon not fully/correctly installing IE(I still had ver 6, I use firefox religiously so no need to update). I got the 17 something MB IE8 install from ms and voila...all my problems where fixed. I was minutes from having to clean install xp, I hope this helps some of you, as it was a life saver for me(not really but it kept me from having to reinstall all my non-default apps and go through the arduous xp install). Truth can become lie, but if lies become truth we're in trouble.

Thanks Rwn, I have also fixed my problem using your advice above. I tried everything I know it would help such as re-registering ddl files etc, but to no luck. This problem was affecting every .chm help files including the ones on MS Office, and I was nearly to clean-install Windows. On seeing you mentioning IE incomplete/ or not fully installed, I remembered that my IE installation did not finish. On re-installing it - ALL PROBLEMS WITH HELP FILES WERE GONE. Once again, thanks for this info. Baiano