Posted by Alvaro G Vicario on 10/16/08 11:19

*** BearItAll wrote/escribió (Wed, 22 Jun 2005 15:56:42 +0100):
> They must be a way, MSN did it when I mistyped my email address in
> the sign up box it told me straight away that it was invalid and it was
> only invalid because I typed a 'd' in place of an 's' in the part before
> the @ sign.

Without sending mail, you can check whether the domain has a valid DNS
entry or even it the server is up and running. It's really hard to check
whether the domain is registered and it's impossible to check whether a
mailbox exists: the VRFY SMTP command is disabled for security/privacy
reasons in many mail servers.

So you can work a lot to create a validation system that offers unreliable
results or you can write a very simple random code system that works 99% of
the time*.


(*) Some mail servers lose mail due to incorrectly configured antispam
systems.

--
-- Álvaro G. Vicario - Burgos, Spain
-- http://bits.demogracia.com - Mi sitio sobre programación web
-- Don't e-mail me your questions, post them to the group
--

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