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Can you block custom extension types?


Article ID: 159576


Updated On:


Data Loss Prevention Enforce


Can you block custom extension types, such as  *.exe,*.bat


Yes. You can use either commas OR newlines; you may not want the spaces after the commas.

For example:  *.exe,*.bat

The Online Help says:

Message Attachment Filename Match

The following table provides details about the options for Message Attachment Filename rules and exceptions:

File Name Specify

The filename to match using the DOS pattern matching language to represent patterns in the filename. Separate the patterns to match with commas or by placing them on separate lines.

Match On

Attachments is preselected. You cannot change this selection for Message Attachment Filename rules.

The following DOS pattern matching expressions are supported:

.   The file name and extension separator

*   Any number of characters (including none)

?  Any single character

Any other characters you enter match exactly.  For example, to match a Word filename that begins with ENG- followed by any eight characters, enter:


If you are not sure it is a Word document, enter:


If you are not sure how many characters follow ENG-, enter:


To match all filenames that begin with ENG- and all filenames that begin with ITA-, enter: