BOAC: All the other security apps can update OK.
If the Ashampoo firewall is the problem here, is it possible that the problem would remain with the firewall turned off? - I've tried that.
SD: The Windows firewall is turned off. DEP has been set for only the essential Windows stuff. I have tried setting DEP to act on everything except the Avast executables...no luck.
With Process Explorer running, I can see the Avast updater starting up.