Check the proxy settings to make sure that they are correct.
   Check to make sure your computer has a working network connection.
   If your computer or network is protected by a firewall or proxy, make sure that Firefox is permitted to access the Web.

I get the error message at the bottom. Yes, my firefox already has "no proxy" selected in the preferences page. I'm able to use Edge fine, but for firefox it does not seem to matter what network I try to connect to. Occasionally it will load some websites like Wikipedia, but then immediately fail anything past that or if I try a different site. Sometimes if I try youtube it will only partially load and then the unable to connect to proxy message will appear in the embedded page videos. Sometimes trying a network reset and then restarting the pc fixes the issue, sometimes it doesn't... I don't know if it has anything to do with this issue but I'm also using NordVPN. Sometimes I am able to get to websites before nord connects itself, sometimes it doesn't matter even if nord does not try to autoconnect. Sometimes it will connect and my internet works fine. I've tried setting up an actual nord proxy through firefox preferences and it doesn't help either. Proxy or no proxy I can't get things to load. When attempting to reach sites I'll get a little message in the bottom left corner of firefox as it tries to reach a website, stuff like: reading img-getpocket.cdn.mozilla.net, looking up *sitename* Don't know what the problem is and I exhausted my limited IT knowledge a while ago, googling for answers hasn't helped. Unable to find the proxy server Firefox is configured to use a proxy server that can’t be found. Check the proxy settings to make sure that they are correct. Check to make sure your computer has a working network connection. If your computer or network is protected by a firewall or proxy, make sure that Firefox is permitted to access the Web.