Okay thanks. I was able to get around it by using the web based activation method instead.
BTW, all firewall/anti-virus services are either completely disabled, turned off or not installed on my FSX PC. It's strictly used for FSX. Most, if not all, of my my Internet access is done through my Secondary PC which is protected.
However, my FSX PC does have Internet access as I was able to activate my other FSDT scenery a few months ago when I did a rebuild.
Weird.....