That might be a solution to the Help Center problem, though I think it's more likely that an update caused this problem. The other one, though, happens on 3 different machines using 2 different versions of IE.
BTW, interesting call on sidhewolf's problem. One of my machines is using the free security software from my ISP, a Zone Alarm clone I believe. Even with the firewall turned off it can prevent certain actions from happening.