I just wanted to add that two of my students in another course have experienced the same problem. The are also working under IE in a secure window. Being thrown out of the quiz prevents their finishing because I have set a delay before the quiz can be re-taken.
You my unenrol me from this course, I just wanted to add that someone else was experiencing the same problem. I assume that the kids are doing something to provoke this but, as I am teaching from a distance, I have no idea what.
J.Lepine