Alternate Ways to Call wp-cron

Using ALTERNATE_WP_CRON

/** Use alternate WP_CRON method with redirects. */
define('ALTERNATE_WP_CRON', true);

Using ALTERNATE_WP_CRON

Run crontab -e
Add the following lines to the end of your crontab file:
# Call wp-cron regularly
*/15 * * * * curl http://www.example.com/wp-cron.php > /dev/null 2>&1