OpenCart Community

Hi there,
Opencart is really a great e-commerce platform for me! But after installed a SSL, found 2 problems that I really can't resolved, need to get some help from experts here.
V1.5.5.1
Store is in a sub domain
Also my store has SEO url enabled, and htaccess saved as .htaccess.
I have admin path rewrite, eg. myadmin
In System setting, the SSL field is "On"

In front end config.php
// HTTP
define('HTTP_SERVER', 'http://subdomain.domain.com/');
define('HTTP_IMAGE', 'http://subdomain.domain.com/image/');

// HTTPS
define('HTTPS_SERVER', 'https://subdomain.domain.com/');
define('HTTPS_IMAGE', 'https://subdomain.domain.com/image/');

in Admin backend config.php
// HTTP
define('HTTP_SERVER', 'http://subdomain.domain.com/myadmin/');
define('HTTP_CATALOG', 'http://subdomain.domain.com/');
define('HTTP_IMAGE', 'http://subdomain.domain.com/image/');

// HTTPS
define('HTTPS_SERVER', 'https://subdomain.domain.com/myadmin/');
define('HTTPS_CATALOG', 'https://subdomain.domain.com/');
define('HTTPS_IMAGE', 'https://subdomain.domain.com/image/');

First Issue:
My store can show up in either http or https for all pages in browser, including admin, account login or checkout. I need it to be show only http on homepage and other pages, except all links that required account login or checkout, need to be in https. For admin, I am not sure, but please see my 2nd issue.

This is related to seo, I think a domain show in both http and https, will split and become lower in Google PageRank. That is why I need my store to be only display in http, except important pages like account and checkout in https.

Before the store was set to all https, but found problem in Google Webmaster account, don't work for indexing ? After changed to http, Google start to index my pages, but if there are http or https 2 versions, thought is not good for ranking, am I right?

So I think I have to add some codes in my .htaccess, kindly advice

Second Issue (admin):
In admin backend, after logged, it go to https, the header and menu tabs become blank. But I can mouse over and see the dropdown menu. It is a bit inconvenience to do works. I need to delete the "s" in browser to make it http, so everything will back to normal.

So I think should re-direct admin from https to http in admin backend, in order to show the header and menu tabs. Kindly advice me on doing this.

Thank you !

Default opencart configuration does not have SSL on he home page. This would have to be done by you or a custom .htaccess / or mod. Default opencart does exactly what you are saying.