How to Configure Mail Filters

Email filters use the criteria that you specify to determine how to handle email messages. The following cPanel interfaces allow you to configure email filters:

Note:

In these interfaces, click + to add a rule, or click - to remove rules.

Filter rules and criteria

The first set of options specifies which part of the email message the system examines to determine whether the message matches your filter parameters.

You can choose from the following options:

Option
Description
From The message sender's address.
Subject The message's subject line.
To

The address to which the sender sent the message.

Note:

Generally, the recipient does not receive the BCC field in an email's header. For this reason, you cannot use theBCC field in a filter.

Reply Address The address at which the sender receives replies.
Body The message's content.
Any Header Any part of the message's header.
Any recipient Any recipient of the message.
Has not been previously delivered The system only examines messages that remain in the queue for delivery.
is an Error Message The system only examines error messages that an auto-response system sends.
List ID The account's mailing lists.
Spam Status Whether Apache SpamAssassin™ marked the message as spam. The Spam Status line begins with Yes or No.
Spam Bar The content of the Spam Bar header that Apache SpamAssassin generated for this message. The more plus signs (+) that Apache SpamAssassin assigns to a message, the greater the likelihood that the system marks the message as spam.
Spam Score

The total number of plus signs (+) in the Spam Bar value, expressed as an integer.

For more information about the Spam Score option, visit the Spam Score table.

Operators

After you select the portion of the email message that the system will examine, select the type of comparison between that portion of the email and the criteria that you enter.

You can choose from the following options:

Option
Description
equals The message exactly matches a defined string.
matches regex

The message matches a regular expression that you define.

Note

The filter text box accepts regular expressions when you select this option, rather than more commonly-used wildcard characters (for example, * or ?).
contains The message a string that you define.
does not contain The message does not contain the defined string.
begins with The message begins with the defined string.
ends with The message ends with the defined string.
does not begin The message does not begin with the defined string.
does not end with The message does not end with the defined string.
does not match The message does not exactly match the defined string.

Spam Score

The following options are only applicable when you select the Spam Score option:

Option
Description
is above (#s only) The message's Spam Score is greater than the number that you define.
is not above (#s only) The message's Spam Score is equal to or less than the number that you define.
is below (#s only) The message's Spam Score is less than the number that you define.
is not below (#s only) The message's Spam Score is greater than or equal to the number that you define.

Important

When you create a filter that uses several operators, the system processes the and operator before the or operator. For example:

  • The system processes A or B and C as A or (B and C).
  • The system processes A and B or C as (A and B) or C.

Criteria

Enter the criteria to use in the text box under the Rules menus. The type of data that you enter determines the comparison that the system performs.

For example, if you select the From and Equals filters, enter user@example.com as the criteria. The system determines that any email fromuser@example.com matches the filter, but does not match seconduser@example.com because it contains additional letters.

Important

Exim converts newlines into spaces in the $message_body field. Do not add \n characters to any body filters that you create.

Actions

When cPanel determines that an email message matches your filter, it handles that message with the any of the following actions that you specify:

Action
Description
Discard Message The system discards the incoming message with no failure notice.
Redirect to email The system forwards the message to another email address that you specify.
Fail with message The system discards the message and automatically send a failure notice to the sender.
Stop Processing Rules The system skips all filter rules.
Deliver to folder The system delivers the message to a specified folder.
Pipe to a program The system sends the incoming message to a specified program. For more information, read the Pipe to a Programsection below.

Pipe to a Program

Important:

Make certain that your script uses the proper file permissions (0700). To change your script's file permissions, run the chmod 0700 myscript.php command, where myscript.php represents your script's location and file name.

Use the Pipe to a Program option to parse and enter email information into a different system. For example, use the Pipe to a Program option to pipe email information to a program that enters email information into a ticket system.

When you use the Pipe to a Program option, enter a path that is relative to your home directory. For example, to use the /home/user/ script.plscript, enter script.pl in the Pipe to a Program text box, where user represents your username.

Note:

If you use PHP, make certain that you appropriately wrap your code in start and end tags.

PHP and Perl hashbangs

To ensure that the script functions properly, the script must be executable and the appropriate hashbang line must exist at the top of the script.

If your script does not include a hashbang, enter the path to the Perl or PHP interpreter in the Pipe to a Program text box. Follow it with the full path to the script, for example:

/usr/local/bin/php /home/john/test.php
/usr/bin/perl /home/john/test.pl

Ref: https://documentation.cpanel.net/display/CKB/How+to+Configure+Mail+Filters