Re^9: Yet Another E-mail Validation Question

Typos are the primary motivator, true.

It's not side-stepping RFC2821 so much as it is working around the widespread switching off of VRFY support, which is a response to spammers abusing VRFY. Mail::CheckUser provides a mechanism that, by default, does not treat a full mailbox as a failure, and the docs suggest against treating a timeout as a failure. What I do in response to timeouts is explain to the user that his address could not be validated "due to temporary network congestion", and bother him to confirm that it's correct. After that, the SMTP server gets to cache and retry as necessary when it's time to actually send email.

I've yet to hear a complaint from a user with a valid email address which has been rejected by these kinds of checks. It's certainly possible that a user could happen along while his DNS administrator is experiencing a fit of incompetency and there are no MX records to be found -- frankly, I consider this to be in the "Not My Problem" category. I'm not aware of it happening yet on any of the sites I administer, but if it becomes a recurrent problem I suppose I'll have to deal with it somehow.

Comment on Re^9: Yet Another E-mail Validation Question

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Re^10: Yet Another E-mail Validation Question by eric256 (Parson) on Apr 22, 2005 at 18:56 UTC
One of those cases where it is usefull to know how it actualy works in eperience agiansn't the realm of the possibilites. So it sounds like for that particular goal it does the right job. Thanks for the info. I think if you are going to send emails that a emailed verification code would still be best because it means most you are sending 1 unwanted email to someone. I'm guessing however that you use that as well and just use Mail::CheckUser to verify the address might be an address, then use further means to make sure it the right users address. ___________ Eric Hodges	[reply]
Re^11: Yet Another E-mail Validation Question by gloryhack (Deacon) on Apr 22, 2005 at 19:27 UTC
You're welcome. :-) I always insist that mailing lists use double opt-in, so I've never been involved (on the server side) in a mail bombing. It's good that we have this all cleared up! Be well.	[reply]