internet explorer add on

Hi all,
Hope I can get help for this.
My wife got a e-card from a friend, when she clicks on the link to view the e-card
I get a message: Information Bar popped up telling me that IE had stopped the site from
installing an Active-X control. When I clicked to install the control (I
certainly trust _this_ site), and then got back the message that "Windows has blocked the software because it cannot verify the publisher." There was no way I could continue.

How do I override this flakey protection that completely prevents me from
viewing the image`s

I tried that and it didnt work, still get same pop up security warning.

If I use firefox, it shows up just fine.
I sure would like to know how to get around it in ie8.