I have done the following as suggested,
1. Start Notepad and open the file <avast4>\Data\avast4.ini
2. Find the section [Common]
3. Add the following line into that section (at the end, beginning... wherever):
SunbeltKPFHack=2
4. Save the changes; avast! self-defense might pop up with a message about avast4.ini being changed, so confirm that
and so far it have worked, I will post back with an update in a couple of days
Cheers, Iain