Well, this is interesting… a dialog just popped up from Avast (see attached image), with “Yes” and “No” buttons but no message!
I suspect it’s nagging me to restart, since Avast updated earlier (to 2014.9.0.2011) and I declined to restart immediately after, but would help if it said so… I’ve no idea what I’m being asked to say “Yes” or “No” to :-\
Certain new elements of avast! will not be running properly or at all until your system is restarted. I’d be more concerned if your popup occurred after the reboot, not before. Let us know if it happens again after you’ve done more than one restart.