Hi, looking to send out a marketing event attachment (flyer) to a group of external people with an accept button that has a return email address in the embedded hyperlink. Question is, is there a way to have a subject line prefilled (or autofill) about the marketing topic on the external senders mail client? I'm thinking just use a standard calendar rsvp in outlook 2016 (and also has accept / decline) perhaps could use something like mail chimp?b sorry sounds like a silly question and its late lol..