I just spent the morning dealing with this. The problem wasn’t that I had a certificate missing. It was that I had an extra.
I started out with my ssl.conf containing my server key and three files provided by my SSL certificate authority:
# Server Certificate:
SSLCertificateFile /etc/pki/tls/certs/myserver.cer
# Server Private Key:
SSLCertificateKeyFile /etc/pki/tls/private/myserver.key
# Server Certificate Chain:
SSLCertificateChainFile /etc/pki/tls/certs/AddTrustExternalCARoot.pem
# Certificate Authority (CA):
SSLCACertificateFile /etc/pki/tls/certs/InCommonServerCA.pem
It worked fine on desktops, but Chrome on Android gave me err_cert_authority_invalid
A lot of headaches, searching and poor documentation later, I figured out that it was the Server Certificate Chain:
SSLCertificateChainFile /etc/pki/tls/certs/AddTrustExternalCARoot.pem
That was creating a second certificate chain which was incomplete. I commented out that line, leaving me with
# Server Certificate:
SSLCertificateFile /etc/pki/tls/certs/myserver.cer
# Server Private Key:
SSLCertificateKeyFile /etc/pki/tls/private/myserver.key
# Certificate Authority (CA):
SSLCACertificateFile /etc/pki/tls/certs/InCommonServerCA.pem
and now it’s working on Android again. This was on Linux running Apache 2.2.