Recently in having to make a WordPress install PCI compliant, the compliance agency required the WP-Admin login to be transmitting login information via HTTPS. Granted we had our SSL Certificate in place correctly, but in order to force WordPress to us HTTPS on it’s login page, drop this code in your wp-config.php file and HTTPS will now work for both your /wp-login.php and /wp-admin URLs:
For more details, reference WordPress Codex on Administration Over SSLFind this useful? Take just a moment and give a $1. Thanks!