InterScanTM Messaging Security Virtual Appliance - Online Help ...

Trend Micro InterScan Messaging Security Virtual Appliance Administrator’s Guide
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Why are email messages from some senders always received as
attachments? Why is the mail body replaced by the disclaimer or
stamp?
When the character set of the stamp is different from the character set of the email
message content, IMSVA will encounter issues inserting the stamp into the message
body after scanning the message. In this situation, IMSVA will create a new email
message, insert the stamp into the message body, and attach the original message. The
message content, however, will not be changed.
How can I specify a keyword expression to represent a blank header for
matching fields such as "From", "To", or "Subject" when creating rules
with the content filter?
If you are going to use a regular keyword expression to represent a blank header, Trend
Micro recommends that you use "^(\s)*$" (without the quotation marks). The
expression "^(\s)*$" (without the quotation marks) represents a blank header or
whitespace characters.
For example, if you want to check if an email message’s "From" header is blank, edit a
rule’s scanning condition as follows:
1. On the Web management console, click Policy > Policy List.
2. Click the link for an existing rule to edit the rule.
3. Click And scanning conditions match.
4. Click Header keyword expressions under the Content section.
5. Click Add to create a new keyword expression.
6. Add the content as "^(\s)*$”" (without the quotation marks).
Why does the message size scan condition not work for encrypted messages?
IMSVA treats encrypted messages as a special type of message. Most scan conditions do
not apply. IMSVA requires the use of the encrypted message scan condition to scan or
perform actions on encrypted messages.