FILE REPUTATION WARNING after update

I updated my AVAST free antivirus . Then I kept getting these messages. They kept reappearing after I closed them. Could the update be suspicious? I restarted my PC and they seem to have stopped. This is a quick screencap of the message.

http://i.imgur.com/QdHy95v.jpg

https://forum.avast.com/index.php?topic=164493.0

does that indicate it is fake?