I have bought Avast pro and tried to start setup, and got following communication:
You are trying to use an old version of the avast! setup.
Instead of using the packages stored in this file, the installer will download and use the latest setup from Internet.Setup GUI was not initialized properly
Then I scanned with Malwarebyte and found and removed Rogue.LiveSecurityPlatinum
It did not help in main problem so I uninstalled all former Avast installation (4 and 5) with Avast uninstal program downloaded from this forum
Still no problem solved. So I guess there is a kind of infection I can not remove.
Attached is current
Malwarebytes log