Third time round: I uninstalled CCleaner, deleted the registry key again, restarted my Trend Micro antivirus and ran the installer again. No Avast offer and no avast install either. This is how it's meant to work.
Third time round: I uninstalled CCleaner, deleted the registry key again, restarted my Trend Micro antivirus and ran the installer again. No Avast offer and no avast install either. This is how it's meant to work.