Avast Secure Line can assist you in blocking hackers on public Wi-Fi and advertisers from tracking everything you do online. However, Avast VPN issues do arise from time to time. One of the causes of Avast VPN not working is a faulty Internet connection. The ISP sometimes prohibits Secure Line VPN clients from running on the network. You should also determine whether all proxy servers should be disabled. Restarting the router is another option. Connect your computer to the Internet once more to see if the Avast VPN problems persist.