If you are having difficulty sending e-mails using a program such as Outlook, Outlook Express, Apple Mail or Thunderbird, please check the following:
Is your ISP (Internet Service Provider) blocking external SMTP servers from being used when you are on their network? Contact your ISP and ask them what SMTP server you should be using.
Ensure that you have your SMTP server setup correctly. The server will be your domain name. You also need to check that you have it setup to authenticate with your mailbox username and password.
If neither of the above appear to be the problem, please contact our support team on firstname.lastname@example.org and we will do our best to assist you