User guide

Configuring an SMTP Proxy Service
User Guide 115
• A string is a wildcard pattern if it contains a question mark (?), an
asterisk (*), or a right parenthesis (().
• A question mark (?) matches any single character.
• An asterisk (*) matches any string, including an empty string.
Denying attachments based on file name patterns
The Content Types tab includes a list of file-name patterns denied by the
Firebox if they appear in email attachments. To add a file-name pattern to
the list, enter a new pattern in the text box to the left of the Add button.
Click Add.
Specifying a deny message
In the Content Types tab, you can enter a message to be shown when a
content type is denied–this message is shown to the recipient only and
not the sender. A default message is provided. Use the variable %t to add
the content type to the message. Use the variable %f to add the file name
pattern to the message.
Adding address patterns
Adding address patterns can be useful for reducing spam content. From
the Incoming SMTP Proxy Properties dialog box:
1 Click the Address Patterns tab.
2 Use the Category drop list to select a category.
3 Type the address pattern in the text box to the left of the Add button.
4 Click Add.
The address pattern appears at the bottom of the pattern list.
Protecting mail servers against relaying
Hackers and spammers may attempt to use an open relay to send mail
from your servers. To prevent this, disable open relay on your mail
servers by restricting the destination to only your own domain.
To further increase protection from mail relaying, modify the SMTP Proxy
settings to allow addresses only from your domain. From the Incoming
SMTP Proxy Properties dialog box:
1 Click the Address Patterns tab.