Mail Delivery

General

You can set up general SMTP-related limits on users' login and inbound/outbound mail delivery.

  1. Go to Mail Delivery > General.
  2. Select Enable SMTP Authentication. When connecting to MailPlus Server via SMTP, clients will have to provide user credentials for login.
  3. Two more authentication options are available:
  4. To stop SMTP clients from auto-forwarding emails, select Disable auto forwarding.
  5. Set up an SMTP profile for MailPlus Server:
  6. Click the External Postmaster button and then the plus icon to add email addresses for external postmasters. External postmaster is set to receive system mails sent to Mailer-daemon and Postmaster aliases from other mail servers.
  7. Click Apply to save the settings.

Delivery

MailPlus Server can send mails through other mail servers while not be exposed to the Internet and subject to possible attacks.

To deliver mails from MailPlus Server:

  1. Go to Mail Delivery > Delivery.
  2. Select a rule type: 
  3. Click Apply to save the settings.

Relay Control

MailPlus Server can send or receive mails for other mail servers.

To relay outbound mails for other mail servers:

  1. Go to Mail Delivery > Relay Control, and in the Relay Outbound Mails section, click Trusted List.
  2. Click Create.
  3. Enter rule name, and specify the IP address or subnet mask of other mail servers.
  4. Click OK to save the settings.

To relay inbound mails for other mail servers:

Please set up a DNS record first, and then go to Domain List to add the mail server, you may refer to the following steps:

  1. Set up an external DNS server for MailPlus Server.
  2. Enter your domain name in the MX record on the external DNS server, and enter the IP address of MailPlus Server in the A record. In this way, other mail servers will be able to send mails to MailPlus Server based on these DNS records.
  3. Set up an internal DNS server for MailPlus Server to find your main mail server.
  4. Enter your domain name in the MX record on the internal DNS server, and enter the IP address of the domain in the A record. The priority of the DNS records on the internal DNS server must be higher than that on the external DNS server.
  5. Go to DSM > Control Panel > Network > General, and tick the Manually configure DNS server checkbox, enter the IP address of the internal DNS server in the Preferred DNS Server field, and enter the IP address of the external DNS server in the Alternative DNS Server field to make sure the internal and external connections of MailPlus Server can work properly. After MailPlus Server receives mails, it will check the MX records of the two DNS servers, and send the mails to the mail server with the higher priority.
  6. Launch MailPlus Server, and go to Mail Delivery > Relay Control, and under the Relay Inbound Mails section, click Domain List.
  7. Click Create.
  8. Enter rule name and domain.
  9. Click OK to save the settings.

Note:

Security

To create black and white lists:

With the black and white lists, the system will reject, discard, or allow certain messages based on various criteria.

  1. Go to Mail Delivery > Security > Black and White Lists.
  2. Select either rule type:
  3. Click Create.
  4. Name the rule and specify its criteria:
  5. Click OK to save the rule.

Note:

To create sender policies:

You can set policies to block emails from senders from unidentifiable domains.

  1. Go to Mail Delivery > Security > Sender Policy.
  2. Enable the following options to suit your needs:
  3. Click Apply to save the settings.

To create connection policies:

You can set policies to block client hosts that cannot be identified or may cause MailPlus Server to overload.

  1. Go to Mail Delivery > Security > Connection Policy.
  2. Enable the following options to suit your needs:
  3. Click Apply to save the settings.

To create advanced security rules:

  1. Go to Mail Delivery > Security > Advanced.
  2. Enable the following options to suit your needs:
  3. Click Apply to save the settings.