Symantec Security 5600 Series, Security 5400 Series,Clientless VPN 4400 Series, Administration Manual

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356 Preventing attacks
Increasing productivity by identifying spam email
8
To apply these settings, create a rule and, on the Antispam tab, check Subject pattern matching .
Related information
For further information related to this topic, see the following:
■
“Adding antispam protection to a rule” on page 358
■
“Understanding and using licenses” on page 86
Reducing false positives
To minimize false positives, you can define a list of sender domains that are not evaluated by the real-
time blacklists. You can also specify email addresses and domains that are allowed to bypass scanning
processes.
Note:
These features are only available for the SMTP protocol.
The topics in this section are:
■
Reducing false positives by bypassing the real-time blacklists
■
Reducing false positives using a custom allow list
Reducing false positives by bypassing the real-time blacklists
If you use the real-time blacklists feature, you might occasionally find that a mail server or the relay
that is making the connection has been incorrectly identified by the blacklist operators as a source of
spam. The security gateway lets you create a custom list of mail transfer agent IP addresses that are
permitted to bypass the real-time blacklist processing.
Ensure that you enable the real-time blacklist servers setting in the appropriate security gateway rule.
You must also have a valid Firewall Base license. If you do not, the security gateway does not attempt to
use this antispam scanning process.
Note: This feature is only available for SMTP.
Prerequisites
None.
To reduce false positives by bypassing the real-time blacklists
1
In the SGMI, in the left pane, under Policy, click Antispam .
2 In the right pane, on the Configuration tab, to the right of the Real-Time blacklisted senders to
allow list, click
Add .
3 In the Blacklisted Senders to Allow dialog box, in the IP address text box, type the IP address of the
mail transfer agent that is permitted to bypass real-time blacklist processing.
4 Click OK .
5
Optionally, do one of the following:
■
To save your configuration now and activate later, on the toolbar, click Save .
■
To activate your configuration now, on the toolbar, click Activate .
When prompted to save your changes, click Yes .
6
To apply these settings, create a rule and, on the Antispam tab, check Senders lists .