Can't update WP

I am currently running WP 4.0.1 and I am receiving this error message trying to update to 4.3. What needs to be done to correct this? My server admin is not helpful.

Warning: An unexpected error occurred. Something may be wrong with WordPress.org or this server’s configuration. If you continue to have problems, please try the support forums. (WordPress could not establish a secure connection to WordPress.org. Please contact your server administrator.) in /var/www/domains/chinablueart.chinablueart.com/docs/wp-includes/update.php on line 295