Your control panel works in cooperation with Qmail mail server, which provides mail services for your domains. After installation the mail server is configured automatically and is ready to serve, however, we recommend that you review the default settings to make sure that they satisfy your needs:
Also notify your customers that they need to specify in their e-mail programs' settings the port 587 for outgoing SMTP connections, and be sure to allow connections to this port in your firewall settings.
With closed relay the mail server will accept only e-mail addressed to the users who have mailboxes on this server. Your customers will not be able to send any mail through your outgoing SMTP server, therefore, we do not recommend closing mail relay.
With relay after authorization, only your customers will be able to receive and send e-mail through your mail server. We recommend that you leave the authorization is required option selected, and specify allowed authentication methods:
A dictionary attack is when someone tries to find out a valid user name and password by running a program that tries different combinations of dictionary words in different languages. Dictionary attacks can be successful because many users choose their passwords carelessly.
Selecting the Use of short and full names is allowed option will allow users to log in to their mail accounts by specifying only the left part of e-mail address before the @ sign (for example, username), or by specifying the full e-mail address (for example, email@example.com).
To avoid possible authorization problems for e-mail users who reside in different domains but have identical user names and passwords, we recommend that you choose the Only use of full mail account names is allowed option.
Once you have set your mail server to support only full mail account names, you will not be able to switch back to supporting short account names until you make sure there are no encrypted passwords for mailboxes and user accounts with coinciding user names and passwords residing in different domains.
Note: If you wish to set up spam protection systems, such as SpamAssassin spam filter, or protection systems based on DomainKeys, DNS blackhole lists or Sender Policy Framework (SPF), proceed to the Setting Up Spam Protection section.