Hello, I am not sure this relates to Avast, but this message just started to appear the very first time the computer rebooted after Avast 5 was installed.
See attached screenshot.
The message is in Italian but the meaning is “LUpdate MFC Application just stopped working - If Windows will be able to find a solution you will be notified etc etc…”
Just to be on the safe side I will now downgrade and revert back to Avast 4