🚀 go-pugleaf

Mark Jacobs wrote:

> hilary.jenkins@grossfahrt.com is valid
> henry.johnson@grossfahrt.com is invalid
> hilary.jenkins@grobfahrt.com is valid

Why would the second one be invalid ? They all have the same syntax.

Or do you mean non existing ?

Hans.

"Mark Jacobs" <http://www.jacobsm.com/mjmsg?Borland%20Newsgroup> wrote in
message news:4471afcd$1@newsgroups.borland.com...

> How do I go about validating both the username and
> domain name parts of an email address?

You would have to use a DNS lookup to get the MX records of the domain.  The
MX records contain the IP addresses of the domain's SMTP servers.  You would
then have to connect to each server, issuing a VRFY command to each one,
until one of them reports success.  Do note, however, that some servers
dsable the VRFY command, unfortunately.


Gambit

Remy Lebeau (TeamB) wrote:
> "Mark Jacobs" <http://www.jacobsm.com/mjmsg?Borland%20Newsgroup>
> wrote in message news:4471afcd$1@newsgroups.borland.com...
>
>> How do I go about validating both the username and
>> domain name parts of an email address?
>
> You would have to use a DNS lookup to get the MX records of the
> domain.  The MX records contain the IP addresses of the domain's SMTP
> servers.  You would then have to connect to each server, issuing a
> VRFY command to each one, until one of them reports success.  Do
> note, however, that some servers dsable the VRFY command,
> unfortunately.

Thanks. I found out that our server does not support the VRFY command, and 
I'm wondering what proportion of SMTP servers do? I also note that some act 
as relays to *any* request from anywhere (I won't publish the host of one in 
particular  :-) ). In my experience, there is still no guaranteed way of 
validating an email address, because, just this luch-time, the DNS server 
was timing out, as our execs played a LAN shoot 'em up! That's difficult to 
program for, unless you know their "timetable" in advance. ;-)
-- 
Mark Jacobs
http://jacobsm.com 

"Mark Jacobs" <www.jacobsm.com/mjmsg.htm?Borland Newsgroup> wrote in message
news:447230b2$1@newsgroups.borland.com...

> I found out that our server does not support the VRFY command

Then you wil not be able to verify users on your own server.

> I'm wondering what proportion of SMTP servers do?

That number is decreasing, unfortunately.  As spamming and abusing
increasing, more and more system admins are closing down the features that
allowed them to do their malicious work, and are implementing tighter
security and validating protocols.

> I also note that some act as relays to *any* request from anywhere
> (I won't publish the host of one in particular  :-) ).

A lot of servers don't support relaying anymore, either.  It makes it harder
for recipient servers to validate the senders.

> there is still no guaranteed way of validating an email address

Nope, unfortunately.


Gambit