Not sure if this will fix the issue of being stuck on ‘waiting for usable network’ for everyone, but I’ve found a fix for it if you’re on Windows 10 (Free version).
Open Task Manager, click a random task, then hit p (for Proton VPN), then end the task(s) affiliated with Proton. I had two in mine both labelled as Proton. Once you’ve done that, reopen Proton and quick connect. That fixed it for me anyway, as I said, not sure how many people are having this issue or if it will help but thought I’d put it out there.
When this happens (barely any times) I just disconnect my internet while it’s on “waiting for a usable network” then I connect it back on and it’s connecting immediately after my computer connects to internet.
A combination of stopping all ProtonVPN tasks & services, restarting ProtonVPN, and unplugging-plugging ethernet cable while it was trying to connect worked for me.
For me, the problem was that my firewall was blocking ProtonVPN. If you’re using Windows and using a different firewall than standard (or using something other than Windows,) check that your firewall has rules to allow Proton.
This happened on my windows 11 laptop and I had to uninstall it completely, download the latest version and reinstall. Connected without issues.
FWIW, when I went to Settings > Apps > Installed apps, I noticed that there were 3 different versions, and even the latest installed version was out of date. So, uninstalled all of them.
a little update: i often get an issue where i get completely stuck in initializing connection no matter what i do, i also already posted here. The only sort of fix i came into today is to manually start ProtonVPN Wireguard service manually from windows services and it appears it will auto connect to the latest location you connected to, however the GUI remains totally unlinked to this service… something has to be fixed i guess