GlassWire is a free background process that keeps tabs on network activity. Recently when I switched my VPN service to NordVPN, I ran into a problem where NordVPN could not connect to any of its servers. After an exhaustive search for the cause, NordVPN identified a setting in GlassWire that was preventing the connection.
GlassWire provides a personal firewall. This prevents malware from using my network for nefarious purposes. On this occasion, it thought that NordVPN was up to no good. To get around the problem, NordVPN suggested a change to GlassWire’s glasswire.conf file. Instead of hostname_enable_lookup = true, the setting should be false. This fixed the problem.