I received a Black Friday notification hawking sun glasses -- see attached screenshot. It apparently was delivered via an iCal invitation. I searched for the sender ("astvn", email address firstname.lastname@example.org) in Spotlight (which returns the invitation under events & reminder) and Mail (which returns no results though the sender appears in the search results people list). Since I cannot find the actual invitation in mail or any other app there appears to be no way to block the sender or to flag this as SPAM. This appears to be a SPAM backdoor. Any suggestions on how to close it? Thanks! --- Post Merged, Nov 25, 2016 --- I found this answer in this very helpful Apple Support Forum thread: https://discussions.apple.com/thread/7611786 I also used the SPAM calendar suggestion to isolate and delete the SPAM event. This is such a pain the ass. I wasted almost an hour on this nuisance.