>They do this by literally sending the people an email. If it does not bounce, the email is validated.
That's a pretty dumb way to validate an email address. You can just end the connection after a successful RCPT TO and no one needs to be the wiser. The method causes a false validation in the case of an intermediate mail relay that accepts everything but that is such a bad idea that no one does that.
That's a pretty dumb way to validate an email address. You can just end the connection after a successful RCPT TO and no one needs to be the wiser. The method causes a false validation in the case of an intermediate mail relay that accepts everything but that is such a bad idea that no one does that.