In the past, I have occasionally gotten this window when I shut down windows but in the last week or so, this message is constant.  I now cannot shut down windows without this popping up and me having to click the button which says "end now".

So, a few questions.  One, what is this and why does it pop up?  Two, how can I correct this?  Third, what are the ramifications if I can't and is it harmful in any way?

As always, thanks for your great assistance.