ping to check for real email addresses

Question

Is there anyway to ping an email address or something such like to check with it is a real working address. I'm not talking about regex or php validate filters etc, but actually checking the address exists??

Answer 1

It is possible, but not reliable to connect to the recipient mailserver and offer a mail, prompting the mailserver to reject or accept the mail. Not all mail servers will check the validity of adresses, so don't rely on it. Similar question here.