Hello. Most, if not all of us, are having this issue right now. It shall be rectified in the program update, and otherwise avast! is working just fine. See the below thread for details, and if you want to read the avast! team’s responses, be sure to read all 4 pages. 
Cheers!
http://forum.avast.com/index.php?board=2;action=display;threadid=3675