jcstauring Hi
I just made a test by sending a test email via Global configuration on your site and it sent successfully. However, with PHP Mail mailer you're using for Mail settings on your site, the email goes to spam box instead of the inbox. You can consider to use SMTP Mail mailer instead.
About the 403 error, it is most likely caused by a problem with the server's 'mod_security' settings. The server thinks that this is a possible security hack and denies access. You can contact your host as they are able to see the ID of the event in the Apache logs and override the security rule. It's server issue.
