Very recently, I've noticed that my IE7 window will simply not close, e.g. when
I click on the "X" in the top right part of the window. At other times, it will
not close when I left-click on the bar at the bottom of the screen and click
"Close". At other times, it will close normally. I don't recall doing anything
that would "modify" any of IE7 settings. Suggestions, please!

Bill