Re: Verifying E-Mail Addresses

I believe the only way to do this would be to have the backend scripting connect to the mx server for the supplied domain, start writing an email to the email address and look for a User Unknown response, then just bail out halfway through
before finishing therefore never sending an email.

Although, not all mail servers mail disclose that information in the same manner, or disclose it at all depending on the configuration.

--
Shane Warner
Director of IT
Answer Plus Inc
Las Vegas, NV 89121
http://www.aplv.com
702-388-7377
shane@xxxxxxxx


Quoting Mister Dookie <misterdookie@xxxxxxxxx>:

Hello list,

Is there a way to verify that an e-mail address
(e.g."johnsmith@xxxxxxxxxxx") is valid and exists or does not exist
(is a fake e-mail address) without actually sending a message to that
address and awaiting the response?

Here's why this is a security issue. Our company administers a small
"municipal-type" 802.11 network where for limited open-access the only
form of ID we require is an e-mail address and a password. We simple
don't have the resources to send out e-mails and then have
verification and so forth. We are trying to prevent users from
entering fake addresses into our system. We want at least a small
amount of accountability.

We would like to be able to do a quick check, say query an IMAP, POP3,
or SMTP and check to see if there is actually an account at that
address without sending a verification e-mail and waiting for users to
click on a link or get something that bounces back. Does something
like that exist?

I do recognize that somebody can enter a valid e-mail address that
does not belong to them, but we are trying to address one issue at a
time. At this point we are just trying to prevent people who give us
"dude@xxxxxxxx" from getting on to our network.

Thanks,
John

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