SMTP Filter

The second tab under SMTP Setup allows you to set the filtering criteria for SMTP messages.

Use the following table for reference while completing this screen.

Allow MAIL FROM command with a null mail address (MAIL FROM: <>)	Check this box to have the SMTP service allow MAIL FROM command with a null mail address (MAIL FROM: <>)
Check mail address and disable invalid addresses when using SMTP	Check this box to have the SMTP service check for valid delivery addresses and disable any invalid email addresses.
Look up the recipient's address when sending mail to this server	Check this box to have the SMTP service check for valid recipient addresses when messages are being sent to this server.
Check the domain of sender's address by DNS query	Check this box to have the SMTP service check the validity of the sender's address using a query to DNS
Connect the sender's mail server checks the sender's address	Check this box to have the SMTP service connects the sender's mail server and than checks the sender's address
Check A or MX of the HELO/EHLO hostname	Check the A record or MX record of the HELO/EHLO Hostname to see if it matches the IP addressUse the Class pull-down menu to select the class of the IP address to be matched. For example: .Class A - Compare first portion of IP address. 119.119.119.119 and 119.51.127.156 match. .Class B - Compare to second portion of IP address. 119.119.119.119 and 119.119.127.156 match. .Class C - Compare to third portion of IP address. 119.119.119.119 and 119.119.119.156 match. .Class D - Compare to fourth portion of IP address. 119.119.119.119 and 119.119.119.119 match.
Reject the HELO/EHLO hostname that is listed in "HELO/EHLO filter"	Check this box to reject email requests from the HELO/EHLO host(s) listed on the HELO/EHLO Filter tab.
Enable SPF(Sender Policy Framework) check	Check this box to enable SPF check. http://www.openspf.org/
Check MAIL FROM matches the address of FROM field in message header	Check this box to check MAIL FROM matches the address of FROM field in message header.
Check RCPT TO matches the address of TO/CC/Delivered-To/Received fields in message header	Check this box to check RCPT TO matches the address of TO/CC/Delivered-To/Received fields in message header.
Enable trap mailbox	Check this box to enable trap mailbox. When some spam tools send a message to this mailbox, so that shielded the ip address for a while
Dealing with spam	SMTP receive mail filtering to the above action, if judged as spam, this message to the following actons: 1. Rejected - SMTP communication process, the direct return of error. 2. Sent the message to mailbox - all the spam sent to the designated-mail. 3. Prepend the mesage's subject with a string - the subject of spam increased [SPAM] string, continue to transmit to the recipient.

.To apply your changes, click the Apply button.
.To cancel current settings and return the screen to its state after the last "Apply" operation, click the Reset button.