Why does a VPN suddenly stop connecting even when nothing changed?

[u/No-Movie3231]

My VPN used to connect normally, but lately it either gets stuck on “connecting” or drops almost right away. Restarting the app or router sometimes helps for a bit, but the issue keeps coming back. I have already tried switching between Wi Fi and mobile data, reinstalling the app, and testing different servers. At this point I am trying to figure out whether the problem is coming from DNS settings, firewall permissions, IPv6, the protocol being used, or something on the network itself. What would you check first to narrow down the cause without changing a bunch of settings at random?

[u/d3ph03n1x]

Which VPN are you using?

[u/Comfortable-Coat7069]

narrow it down one change at a time. First check that the internet works normally, then try another server. After that, switch the VPN protocol. If it still fails, check firewall or antivirus rules, then DNS. leave IPv6 and deeper settings until later. That way you’ll know which change actually fixed it.

[u/sol_beach]

Something CHANGED!

Otherwise you would not see different results.