Is there a mechanism for verifying an e-mail address exists before sending?

closed as not a real question by pauska, Holocryptic, Iain, mfinni, jscott Aug 16 '11 at 13:40

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  • "Exists" where? As in, already sent from the same client software? That would need to be implemented in the client software and thus this is a SU question. If you mean "already sent by the mail server", then no, I've never heard of such a thing. Monitoring systems send out identical emails (all the bloody time), as an example of why you wouldn't implement such a feature in a mailserver. – mfinni Aug 16 '11 at 13:35
  • @mfinni, given his primary account is SO, I'm thinking this is a program that is accepting an e-mail address and trying to verify it's validity without actually sending an e-mail. – Chris S Aug 16 '11 at 13:48

RFC 2821's "VRFY" SMTP command is supposed to do that but, due to spammers abusing this command for validating mail addresses lists it's often disabled on the servers and SMTP gateways.

  • If by "email" you and the OP mean "email address", then yes, VRFY is the mostly-unusable solution. – mfinni Aug 16 '11 at 13:36

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