A new user in my forum sent spam messages. I became aware because I received many bounced emails titled "Mail delivery failed: returning message to sender" . I assume these are member's email addresses that are no longer valid. I banned the user but the undeliverable emails kept coming. I then deleted the user and still I'm getting undeliverable emails returning to my forum email account. Is it possible for the deleted user to keep sending spam? How exactly are they sending these messages because I didn't see see anything in my forum messages inbox?
Message content looks like this:
Dear member name,
„katrina“ sent you a message on My forum:
What do you think about ..... without a condom? Write to me - > vk.cc/as76sY