AutoSSL requires that port 80 is open and not in use on the server. If you have run autoSSL and the configuration has failed it is likely that one of the following problems has occurred.
- Timeout during connect (likely firewall problem)
- The Certificate Authority failed to download the challenge files from the temporary standalone webserver started by Certbot on port 80. Ensure that the listed domains point to this machine and that it can accept inbound connections from the internet.
You will need to review your firewall settings and ensure that port 80 is open.
