The Attachment is
true file typecriteria allows you to create policy rules that take actions on messages based on the true file type of attachments a message contains.
NoteWhere the Attachment is
 
file name or extensioncriteria makes decisions based on just file names and/or extensions, the Attachment is true file typecriteria scans the headers of the files themselves for the identifying signatures.  | 
Procedure
- On the Scanning Criteria tab, click Advanced.
 - Select the Attachment is
true file type
criteria. - Click the 
true file type
link.The Attachment True File Type screen appears. - From the drop-down list, select Selected true file types or Not selected true file types.
 - Select the true file types for Trend Micro Email
                           Security to
                        match on.

Note
- 
For Microsoft Office files of version 2007 or later, Trend Micro Email Security supports attachment true file type detection only when the files are not encrypted.
 - 
The Compressed file type of other includes only the following file types:
ar,arc,amg,lzw,cab,lha,pklite,diet,lzh, andlz. 
 - 
 
		