Why do certain websites suddenly stop working for me?

On Mon, 4 Dec 2017 17:39:26 -0600, VanguardLH wrote:

Doomsdrzej wrote:

It would have to be something which affects both browsers such as a
firewall program.

Does the Windows 10 firewall do anything regarding outbound connections?
It can reject unsolicited inbound connection requests but, as I recall,
does nothing about outbound connections. Of course, the OP might've
installed a more robust 3rd party firewall.

Or the OS configured to use a local proxy instead of going direct to the
Internet. So another place to check is:

Internet Options - Connections - LAN Settings

If the OP is using a VPN, it going unresponsive or dead will kill all
Internet access if it is still enabled (to intercept all network
traffic). A proxy can be dead despite it is currently enabled.

I was thinking about the proxy as well but I figured that there was a
software confusion. In his case, I'd probably try to fix the problem
this way:

1) check to see if hosts was modified (it wasn't)
2) check for firewall software of any sort (probably bundled with some
free anti-virus solution)
3) check LAN settings (I doubt that there is anything there but it's
worth a look)
4) run sfc /scannow (using the Command Prompt in Administrative Mode)
to verify if some files crucial to Internet communication might have
been corrupted