I recently installed an SSL certificate on a subdomain following the steps at cPanel. Lets just say the domain is example.com and the subdomain is sub.example.com.

1. I updated the userdata file for the subdomain and changed the IP address to the IP I wanted to use
2. I updated the example.com zone file and changed the IP for the A Name for the subdomain to the IP I wanted to use
3. Using domain tools I checked that sub.example.com resolved to the new IP which it does.
4. I then installed an SSL certificate on example.com and then on sub.example.com

When I visit http://sub.example.com I get the default Apache account screen, and when I visit https://sub.example.com I get the cPanel 404 page. If however I enter https://sub.example.com/admin (the location of my admin section) the page loads and I can login.

I thought that this might be a propagation issue however as the subdomain resolves to the IP and I can reach the admin page I suspect it is not a propagation issue and possibly an incorrect zone file.

Any thoughts?