system
10
@AlphaUMi,
Besides the clean install, have you followed DavidR’s suggestion:
Be aware that you can’t just force database updates too frequently (they would fail anyway).
Also, remove firewall rules related to Avast so they can be re-created, and don’t forget to reboot.
An additional question: Do you have normal access to internet using other tools (web browser, Windows updates, Email Clients…)?