Reply #12 indicates he is running IE in protected mode.
I know that, which is why I mentioned the AOS add-on as a possible conflict, as previously the same issues were found when the SmartSceeen was also enabled.
I still don't know how the AOS got installed on IE11, unless it remained from an earlier installation of avast. If a clean install of avast 17.4.2294 were made I don't know if avast would install the AOS on IE11.
It is a bit of a moot point as the OP has made his choice as to what to disable/remove, his system, his choice.