I am looking at trying to create a transport rule to block ANY and ALL attachments in the Exchange 2013 environment.
Test 1 was creating a rule using "Any attachment is greater than or equal to..." 0kb and found that this will block any email that is sent whether it actually has an attachment or not.
Test 2 was creating a rule using "Any attachment's file name matches...". While using RegEx, for example [a-z0-9], I have been able to block emails with attachments. The issue with this is if the body of the email has a large amount of information the email will be blocked even if the email does not contain any attachments.
Anyone out there have any experience with blocking all attachments in their environment?
-Coupe