I got an email today (actually two - one on two different addresses), but it was completely empty!
No sender name, no message line, and no message. What the heck is that all about?
Some spammers use that as a sort of email ping. If they don’t get a “user not found” kind of reply, they know the emaill addy is alive.
How do they do that?
I asked this awhile back and got some answers: here