Get better customers :-) Incidentally: how do your customers know how you entered their email address? That's a matter that is at the discretion of the mailser

Get better customers :-) Incidentally: how do your customers know how you entered their email address? That's a matter that is at the discretion of the mailserver software; it can be automatically rewritten. What you typed into your mailer isn't guaranteed to be reflected in any of the headers the recipient sees. Far from it.