Our junkmail filter works on a quantative basis, filtering message to which we receive more than 100 identical/similar looking copies of.
Messages with no text/body are ignored completely. If you are sending yourself an attachment without any text in the body then you may be experiencing this problem.
From the website above you will be able to view/nominate any message filter as junk to the global whitelist for the university, so future messages are not filtered.
You can also subscribe to a weekly bulk-summary email. Every monday a summary of the email that was rejected from your account as spam will be emailed to you. You can subscribe to the summary by visiting: