As the all the posts shown here before yours have said, you need to make a small edit to your YOUR_ADMIN/includes/configure.php file, and copy the HTTPS_SERVER definition into your HTTP_SERVER definition, so that both are the same.
ie:
define('HTTP_SERVER', 'https://www.example.com');
define('HTTPS_SERVER', 'https://www.example.com');
Don't do the same to your non-admin configure.php. This is only necessary on the admin side.
Is that clear yet?
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