Originally Posted by till
Your problem is not ispconfig nor the ssl certificate created by ispconfig as you currently dont use the certificate created by ispconfig. To me it looks like you enabled some kind of default ssl vhost in centos that is blocking the ssl port, so that a default cert is used and not the one created by ispconfig. Check the apache config of centos and disable the default ssl vhost and default ssl cert. Then restart apache.
I'll give that a ago. Thanks for the reply.