SSL/TLS Certificate Chain Issues

For errors involving “incomplete chain”, see:

• ssl certificate - How do you fix an incomplete SSL chain - Super User
• GitHub - zakjan/cert-chain-resolver: SSL certificate chain resolver

• [SSL certificate chain resolver

  certificatechain.io](https://certificatechain.io/)

My problem turned out to be very simple – I had left the SSLCertificateChainFile directive commented out.