We just upgraded our Cisco Ironport C170 to AsyncOS 13.0.  We have an inhouse Exchange 2010 server. Now outbound emails that are in HTML format have a winmail.dat attachment. This attachment causes some email platforms (like Yahoo) to treat the email...

There is a known defect in IE 11 and Java that prevents secure mail recipients from being able to open PDF attachments. See https://tools.cisco.com/bugsearch/bug/CSCut80868 I believe Workaround #2 should be to DISABLE the applet in the encryption pro...