The certificate in /etc/httpd/conf/httpd.pem expired today. My first attempt to replace the certificate resulted in Apache refusing to start. I've now managed to create a new certificate with exactly the same properties as the original but valid for another year and Apache is running OK for HTTP access on port 80. I can access webmail via HTTPS but connections for Plesk on port 8443 fail with "Connection refused"
The other recent event is that what we thought was an unused domain has just been deleted. The domain was called default-domain.co.uk, this came with the system and we never used it but I'm starting to wonder if it might have been relevant for Plesk, in which case how do I get myself out of this hole?