I have a computer which has stopped connecting to a website.
Normally this computer would just get rebuilt with the standard image we have for the computer, but there's a lot of bespoke software which requires reinstallation which is always very difficult and can take up to a day.
One website, regularly used, works everywhere else. This computer refuses to acknowledge its SSl certificate and refuses to connect. If I ping the domain, it is unsuccessful. If I add the domain and the IP to the hosts file this is ignored. The message I get from ping is 'General failure'.
We don't have any URL or domain filter, Pihole, or any special rules. there isn't a proxy or squid.
So far I have tried: sfc /scannow, ipconfig /flushdns, netsh winsock reset, adwcleaner, chkdsk /f, cleared cookies and cache multiple times, tried three different web browsers, all to no avail. I have set a static IP address and Google DNS addresses, and very occasionally it works. By the time the user tries it goes back to 'This page cannot be displayed' or SSL certificate errors.
It's a letsencrypt certificate and I have also tried installing the intemediary certificate but no difference.
Are there any other things I can try to resolve this problem?