I ran into big connectivity issues with ProtonVPN which forced me to reinstall ZorinOS. I followed the installation instructions to the letter and the service worked fine for half an hour. Then after a suspension and a couple of restarts I lost all connectivity and I have not been able to re-establish it.
I tried to uninstall ProtonVPN from the terminal with the instructions using the Smartphone and succeeded, but there was nothing to do ... I would be tempted to try again to install ProtonVPN as it worked fine for a while, but I'm afraid to run into the same problems. Connectivity from the "cable network settings" seemed fine.
This is how the network settings looked ... like now after reinstallation.
I also had problems with installing ProtonVPN as it seems so did other people ..... please click on the magnifying glass and type ProtonVPN ...... here is just a sample of what you will find ....
[ProtonVPN working - but with issueGeneral Help
zorin-os
Aug '21 - ...did a fresh install of Zorin OS, loving it so far. With a bit of teeth-pulling I managed to get the ProtonVPN CLI installed, and its working BUT I have noticed whenever I run sudo-apt get update, I get the fol...](ProtonVPN working - but with issue)
[Big problems with ProtonVPNGeneral Help
zorin-os-16
1h - Hi, I ran into big connectivity issues with ProtonVPN which forced me to reinstall ZorinOS. I followed the installation instructions to the letter and th...](Big problems with ProtonVPN)
I reinstalled ProtonVPN on the fresh Zorin OS16 installation. For the moment everything works fine ... I inquired and found that the VPN has some bugs that can totally break the connection, but there is a command that is used in these cases to reestablish it.
This is protonvpn-cli ks --off and according to the information it works.
I'll be monitoring and letting you know.
I had more or less the same problem, multiple times.
When I use ProtonVPN with the KillSwitch function on and I switch off the computer without disconnecting the VPN, my internet connection will be gone for good. The problem seems to be a misconfiguration in the DNS, which cannot be fixed by changing the DNS settings in the network configuration tabs. I tried to figure it out in all kinds of config files, but I'm not experienced enough with Linux to fix it persistently. I guess the command mentioned by @diefis is likely to help, though.
Only thing that prevented me from re-installing a second time (didn't know about that cli command) was a system restore with TimeShift.
The phenomenon doesn't occur on my Windows machines or Android. I reported it to Proton.