I use webex quite frequently and have been using it on Internet Explorer 10 for a long time. I upgraded to Internet Explorer 11 yesterday, and today when I tried to join a WebEx meeting, it took me to the WebEx setup screen instead of into the meeting. Clicking on the "Setup" button did not seem to do anything. At one point, I was finally able to get the WebEx installer to run, and after agreeing to let it run, the installer finished and I still can't get into WebEx meetings. My guess is that some security setting is blocking it from running, but I could not find any indication of what was causing the problem.