SMTP Host for BT Openworld*
| ISP | SMTP host |
| BT (Broadband)* | smtp.btclick.com |
| BT Click* | smtp.btclick.com |
| BT Connect* | smtp.btconnect.com |
| BT Internet* | mail.btinternet.com |
| BT Openworld* | mail.btopenworld.com |
* You need to contact BT Internet and request they allow SMTP relaying for your domain. Authentication with your BT user name and password is no longer sufficient.