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testing email deliverability...

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  testing email deliverability... The Natural Philosopher <tnp@invalid.invalid> - 2014-06-05 01:48 +0100
    Re: testing email deliverability... Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> - 2014-06-04 18:40 -0700
      Re: testing email deliverability... Denis McMahon <denismfmcmahon@gmail.com> - 2014-06-05 02:05 +0000
        Re: testing email deliverability... Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> - 2014-06-04 19:17 -0700
      Re: testing email deliverability... Rahul <nospam@invalid.invalid> - 2014-06-05 07:11 +0000
      Re: testing email deliverability... Rahul <nospam@invalid.invalid> - 2014-06-05 11:08 +0000
        Re: testing email deliverability... Marc Haber <mh+usenetspam1118@zugschl.us> - 2014-06-14 11:53 +0200
          Re: testing email deliverability... Rahul <nospam@invalid.invalid> - 2014-06-14 18:34 +0000
            Re: testing email deliverability... Marc Haber <mh+usenetspam1118@zugschl.us> - 2014-06-15 08:54 +0200
    Re: testing email deliverability... "Tony Marston" <TonyMarston@hotmail.com> - 2014-06-05 03:47 +0100
      Re: testing email deliverability... Eli the Bearded <*@eli.users.panix.com> - 2014-06-05 04:53 +0000
        Re: testing email deliverability... Richard Kettlewell <rjk@greenend.org.uk> - 2014-06-05 09:13 +0100
          Re: testing email deliverability... Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> - 2014-06-05 08:05 -0700
            Re: testing email deliverability... The Natural Philosopher <tnp@invalid.invalid> - 2014-06-05 16:21 +0100
            Re: testing email deliverability... Jerry Stuckle <jstucklex@attglobal.net> - 2014-06-05 11:27 -0400
            Re: testing email deliverability... Mike McGinn <mikemcginn@mcginnweb.net> - 2014-06-05 16:31 +0000
              Re: testing email deliverability... "Peter J. Holzer" <hjp-usenet3@hjp.at> - 2014-06-05 21:15 +0200
        Re: testing email deliverability... Arno Welzel <usenet@arnowelzel.de> - 2014-06-09 11:30 +0200
          Re: testing email deliverability... Eli the Bearded <*@eli.users.panix.com> - 2014-06-09 23:08 +0000
            Re: testing email deliverability... Arno Welzel <usenet@arnowelzel.de> - 2014-06-10 11:08 +0200
    Re: testing email deliverability... Sam <sam@email-scan.com> - 2014-06-04 22:04 -0500
      Re: testing email deliverability... Jerry Stuckle <jstucklex@attglobal.net> - 2014-06-04 23:27 -0400
      Re: testing email deliverability... The Natural Philosopher <tnp@invalid.invalid> - 2014-06-05 05:37 +0100
        Re: testing email deliverability... Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> - 2014-06-04 21:55 -0700
          Re: testing email deliverability... The Natural Philosopher <tnp@invalid.invalid> - 2014-06-05 06:17 +0100
        Re: testing email deliverability... Chuck Anderson <cycletourist@invalid.invalid> - 2014-06-05 21:36 -0600
          Re: testing email deliverability... Jerry Stuckle <jstucklex@attglobal.net> - 2014-06-06 09:41 -0400
            Re: testing email deliverability... Denis McMahon <denismfmcmahon@gmail.com> - 2014-06-06 14:37 +0000
              Re: testing email deliverability... The Natural Philosopher <tnp@invalid.invalid> - 2014-06-06 16:46 +0100
                Re: testing email deliverability... Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> - 2014-06-06 10:39 -0700
                  Re: testing email deliverability... Jerry Stuckle <jstucklex@attglobal.net> - 2014-06-06 14:22 -0400
                  Re: testing email deliverability... The Natural Philosopher <tnp@invalid.invalid> - 2014-06-06 20:54 +0100
                    Re: testing email deliverability... Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> - 2014-06-06 13:22 -0700
                    Re: testing email deliverability... Eli the Bearded <*@eli.users.panix.com> - 2014-06-06 21:55 +0000
                      Re: testing email deliverability... Chris Davies <chris-usenet@roaima.co.uk> - 2014-06-09 13:56 +0100
                    Re: testing email deliverability... Marc Haber <mh+usenetspam1118@zugschl.us> - 2014-06-14 11:55 +0200
    Re: testing email deliverability... Jerry Stuckle <jstucklex@attglobal.net> - 2014-06-04 23:05 -0400
    Re: testing email deliverability... "AvdB" <nomail@example.invalid> - 2014-06-05 12:59 +0200
      Re: testing email deliverability... The Natural Philosopher <tnp@invalid.invalid> - 2014-06-05 13:51 +0100
    Re: testing email deliverability... Adrienne Boswell <arbpen@yahoo.com> - 2014-06-05 18:39 +0000
      Re: testing email deliverability... Eli the Bearded <*@eli.users.panix.com> - 2014-06-05 20:46 +0000
        Re: testing email deliverability... Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> - 2014-06-05 14:41 -0700
          Re: testing email deliverability... Eli the Bearded <*@eli.users.panix.com> - 2014-06-06 22:26 +0000
        Re: testing email deliverability... Adrienne Boswell <arbpen@yahoo.com> - 2014-06-05 22:21 +0000
    Re: testing email deliverability... James Moe <jimoeDESPAM@sohnen-moe.com> - 2014-06-05 13:14 -0700
    Re: testing email deliverability... Arno Welzel <usenet@arnowelzel.de> - 2014-06-06 14:11 +0200
    Re: testing email deliverability... Chris Davies <chris-usenet@roaima.co.uk> - 2014-06-09 13:53 +0100
    Re: testing email deliverability... don.schueler@gmail.com - 2014-07-18 03:45 -0700

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#11168

The Natural Philosopher writes:

> what I want is a function like
>
> is_valid_mail("user12345@gmail.com")
>
> that will return true or false if gmail accepts the user as known (yes the  
> spam is always @gmail.com) WITHOUT having to write a dns mx lookup, then  
> connect to socket 25 and etc etc etc..

I'm afraid that you will have to wait until someone invents a telepathic  
computer, that will be able to accomplishing such an amazinf feat.

Until then, unfortunately, a number of inconvenient laws of physics of this  
universe will prevent anyone from determining whether an email address is  
deliverable without looking up its MX server, and connecting to the MX  
server's port 25.

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#11170

On 6/4/2014 11:04 PM, Sam wrote:
> The Natural Philosopher writes:
>
>> what I want is a function like
>>
>> is_valid_mail("user12345@gmail.com")
>>
>> that will return true or false if gmail accepts the user as known (yes
>> the spam is always @gmail.com) WITHOUT having to write a dns mx
>> lookup, then connect to socket 25 and etc etc etc..
>
> I'm afraid that you will have to wait until someone invents a telepathic
> computer, that will be able to accomplishing such an amazinf feat.
>
> Until then, unfortunately, a number of inconvenient laws of physics of
> this universe will prevent anyone from determining whether an email
> address is deliverable without looking up its MX server, and connecting
> to the MX server's port 25.
>

Even then you don't know if the email address is valid.  May mail 
servers are set to accept and trash invalid email addresses.  This is 
because spammers would send emails to random accounts at an email 
address; if they didn't get a reject they knew the address was OK.


-- 
==================
Remove the "x" from my email address
Jerry Stuckle
jstucklex@attglobal.net
==================

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#11171

On 05/06/14 04:04, Sam wrote:
> The Natural Philosopher writes:
>
>> what I want is a function like
>>
>> is_valid_mail("user12345@gmail.com")
>>
>> that will return true or false if gmail accepts the user as known (yes
>> the spam is always @gmail.com) WITHOUT having to write a dns mx
>> lookup, then connect to socket 25 and etc etc etc..
>
> I'm afraid that you will have to wait until someone invents a telepathic
> computer, that will be able to accomplishing such an amazinf feat.
>
> Until then, unfortunately, a number of inconvenient laws of physics of
> this universe will prevent anyone from determining whether an email
> address is deliverable without looking up its MX server, and connecting
> to the MX server's port 25.
>
I meant without me having to write such code,, but it seems someone 
already hass..

http://www.tienhuis.nl/files/email_verify_source.php


-- 
Ineptocracy

(in-ep-toc’-ra-cy) – a system of government where the least capable to 
lead are elected by the least capable of producing, and where the 
members of society least likely to sustain themselves or succeed, are 
rewarded with goods and services paid for by the confiscated wealth of a 
diminishing number of producers.

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#11173

["Followup-To:" header set to comp.os.linux.misc.]

On 2014-06-05, The Natural Philosopher <tnp@invalid.invalid> wrote:
>
> I meant without me having to write such code,, but it seems someone 
> already hass..
>
> http://www.tienhuis.nl/files/email_verify_source.php

As I and others have already stated, this method is not reliable in
general, as some MXs will accept all email for its domains whether
the destination address is valid or not, in order to defeat exactly this
sort of query (done by spammers, but what defeats them defeats this
too).

All this script will do is tell you whether the MX accepted the message.
It can never tell you whether the MX delivered it to a valid mailbox,
discarded it, or generated a bounce.

--keith

-- 
kkeller-usenet@wombat.san-francisco.ca.us
(try just my userid to email me)
AOLSFAQ=http://www.therockgarden.ca/aolsfaq.txt
see X- headers for PGP signature information

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#11174

On 05/06/14 05:55, Keith Keller wrote:
> ["Followup-To:" header set to comp.os.linux.misc.]
>
> On 2014-06-05, The Natural Philosopher <tnp@invalid.invalid> wrote:
>>
>> I meant without me having to write such code,, but it seems someone
>> already hass..
>>
>> http://www.tienhuis.nl/files/email_verify_source.php
>
> As I and others have already stated, this method is not reliable in
> general, as some MXs will accept all email for its domains whether
> the destination address is valid or not, in order to defeat exactly this
> sort of query (done by spammers, but what defeats them defeats this
> too).
>
> All this script will do is tell you whether the MX accepted the message.
> It can never tell you whether the MX delivered it to a valid mailbox,
> discarded it, or generated a bounce.
>
most people these days reject early: that's happened along with 
secondary MX targets that store and forward to reduce the amount of mail 
being sent as bounces.

So I think that snippet will indeed solve the worst of my problems

I'll test it later on and see.



> --keith
>


-- 
Ineptocracy

(in-ep-toc’-ra-cy) – a system of government where the least capable to 
lead are elected by the least capable of producing, and where the 
members of society least likely to sustain themselves or succeed, are 
rewarded with goods and services paid for by the confiscated wealth of a 
diminishing number of producers.

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#11191

The Natural Philosopher wrote:
> On 05/06/14 04:04, Sam wrote:
>> The Natural Philosopher writes:
>>
>>> what I want is a function like
>>>
>>> is_valid_mail("user12345@gmail.com")
>>>
>>> that will return true or false if gmail accepts the user as known (yes
>>> the spam is always @gmail.com) WITHOUT having to write a dns mx
>>> lookup, then connect to socket 25 and etc etc etc..
>>
>> I'm afraid that you will have to wait until someone invents a telepathic
>> computer, that will be able to accomplishing such an amazinf feat.
>>
>> Until then, unfortunately, a number of inconvenient laws of physics of
>> this universe will prevent anyone from determining whether an email
>> address is deliverable without looking up its MX server, and connecting
>> to the MX server's port 25.
>>
> I meant without me having to write such code,, but it seems someone 
> already hass..
>
> http://www.tienhuis.nl/files/email_verify_source.php

I feel I'm about to step into a giant pile of doo, but .... Some years 
back I used a Windows program from Analogx called listmaster pro to 
verify email addresses manually (it is designed to be used with large 
mail lists.  I never verified more than several at a time).  It always 
gave me correct positive and negative results.  It seems to me that, in 
general, an email address can be verified as a valid mailbox - or not.  
There are no guarantees, of course, but this program always gave me the 
correct result.

-- 
*****************************
 Chuck Anderson • Boulder, CO
  http://cycletourist.com
 Turn Off, Tune Out, Drop In
*****************************

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#11196

On 6/5/2014 11:36 PM, Chuck Anderson wrote:
> The Natural Philosopher wrote:
>> On 05/06/14 04:04, Sam wrote:
>>> The Natural Philosopher writes:
>>>
>>>> what I want is a function like
>>>>
>>>> is_valid_mail("user12345@gmail.com")
>>>>
>>>> that will return true or false if gmail accepts the user as known (yes
>>>> the spam is always @gmail.com) WITHOUT having to write a dns mx
>>>> lookup, then connect to socket 25 and etc etc etc..
>>>
>>> I'm afraid that you will have to wait until someone invents a telepathic
>>> computer, that will be able to accomplishing such an amazinf feat.
>>>
>>> Until then, unfortunately, a number of inconvenient laws of physics of
>>> this universe will prevent anyone from determining whether an email
>>> address is deliverable without looking up its MX server, and connecting
>>> to the MX server's port 25.
>>>
>> I meant without me having to write such code,, but it seems someone
>> already hass..
>>
>> http://www.tienhuis.nl/files/email_verify_source.php
>
> I feel I'm about to step into a giant pile of doo, but .... Some years
> back I used a Windows program from Analogx called listmaster pro to
> verify email addresses manually (it is designed to be used with large
> mail lists.  I never verified more than several at a time).  It always
> gave me correct positive and negative results.  It seems to me that, in
> general, an email address can be verified as a valid mailbox - or not.
> There are no guarantees, of course, but this program always gave me the
> correct result.
>

And how did it know?

For instance - I have three domains.  You can send and email to any 
address at any of the three.  But unless it's a valid address, the email 
ends up in /dev/null.


-- 
==================
Remove the "x" from my email address
Jerry Stuckle
jstucklex@attglobal.net
==================

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#11197

On Fri, 06 Jun 2014 09:41:05 -0400, Jerry Stuckle wrote:

> On 6/5/2014 11:36 PM, Chuck Anderson wrote:

>> I feel I'm about to step into a giant pile of doo, but .... Some years
>> back I used a Windows program from Analogx called listmaster pro to
>> verify email addresses manually

> And how did it know?

> For instance - I have three domains.  You can send and email to any
> address at any of the three.  But unless it's a valid address, the email
> ends up in /dev/null.

Which brings us back round to:

The only way to guarantee that an email address is actually going to the 
entity that entered it on your form is to send a verification code to the 
email address.

And even then, I suspect that there are some smart spamming systems out 
there that have email addresses and use eg curl to process the email 
verification links (which is why I use entity and not person above).

-- 
Denis McMahon, denismfmcmahon@gmail.com

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#11199

On 06/06/14 15:37, Denis McMahon wrote:
> On Fri, 06 Jun 2014 09:41:05 -0400, Jerry Stuckle wrote:
>
>> On 6/5/2014 11:36 PM, Chuck Anderson wrote:
>
>>> I feel I'm about to step into a giant pile of doo, but .... Some years
>>> back I used a Windows program from Analogx called listmaster pro to
>>> verify email addresses manually
>
>> And how did it know?
>
>> For instance - I have three domains.  You can send and email to any
>> address at any of the three.  But unless it's a valid address, the email
>> ends up in /dev/null.
>
> Which brings us back round to:
>
> The only way to guarantee that an email address is actually going to the
> entity that entered it on your form is to send a verification code to the
> email address.
>
> And even then, I suspect that there are some smart spamming systems out
> there that have email addresses and use eg curl to process the email
> verification links (which is why I use entity and not person above).
>
I juts love all this 'guarantee' when getting spam don from 99 to 1 
would be a satisfactory result.

I don't care if I get false negatives ads long as the 99 true negatives 
get rejected.


-- 
Ineptocracy

(in-ep-toc’-ra-cy) – a system of government where the least capable to 
lead are elected by the least capable of producing, and where the 
members of society least likely to sustain themselves or succeed, are 
rewarded with goods and services paid for by the confiscated wealth of a 
diminishing number of producers.

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#11201

["Followup-To:" header set to comp.os.linux.misc.]

On 2014-06-06, The Natural Philosopher <tnp@invalid.invalid> wrote:
>
> I juts love all this 'guarantee' when getting spam don from 99 to 1 
> would be a satisfactory result.

You will almost certainly not get down to 99:1 with any method that
doesn't involve sending mail out with a token, and waiting for the user
to ack the token.  My WAG is you might get down to 50:50.  Other folks
might have different, better-informed guesses.

--keith



-- 
kkeller-usenet@wombat.san-francisco.ca.us
(try just my userid to email me)
AOLSFAQ=http://www.therockgarden.ca/aolsfaq.txt
see X- headers for PGP signature information

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#11202

On 6/6/2014 1:39 PM, Keith Keller wrote:
> ["Followup-To:" header set to comp.os.linux.misc.]
>
> On 2014-06-06, The Natural Philosopher <tnp@invalid.invalid> wrote:
>>
>> I juts love all this 'guarantee' when getting spam don from 99 to 1
>> would be a satisfactory result.
>
> You will almost certainly not get down to 99:1 with any method that
> doesn't involve sending mail out with a token, and waiting for the user
> to ack the token.  My WAG is you might get down to 50:50.  Other folks
> might have different, better-informed guesses.
>
> --keith
>
>
>

Keith,

I don't have any figures, either, but I would say your guess sounds 
pretty good.

And of course there are always those spammers with the throw-away email 
addresses.  Valid addresses, but still spam.

-- 
==================
Remove the "x" from my email address
Jerry Stuckle
jstucklex@attglobal.net
==================

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#11203

On 06/06/14 18:39, Keith Keller wrote:
> ["Followup-To:" header set to comp.os.linux.misc.]
>
> On 2014-06-06, The Natural Philosopher <tnp@invalid.invalid> wrote:
>>
>> I juts love all this 'guarantee' when getting spam don from 99 to 1
>> would be a satisfactory result.
>
> You will almost certainly not get down to 99:1 with any method that
> doesn't involve sending mail out with a token, and waiting for the user
> to ack the token.  My WAG is you might get down to 50:50.  Other folks
> might have different, better-informed guesses.
>
> --keith
>
>
>
On te contrary test show that testing gmail with a rcpt to: 
invalid@gmail.com  gets an instant naff off. So it looks like 100% will 
work.


-- 
Ineptocracy

(in-ep-toc’-ra-cy) – a system of government where the least capable to 
lead are elected by the least capable of producing, and where the 
members of society least likely to sustain themselves or succeed, are 
rewarded with goods and services paid for by the confiscated wealth of a 
diminishing number of producers.

[toc] | [prev] | [next] | [standalone]

#11204

On 2014-06-06, The Natural Philosopher <tnp@invalid.invalid> wrote:
>
> On te contrary test show that testing gmail with a rcpt to: 
> invalid@gmail.com  gets an instant naff off. So it looks like 100% will 
> work.

...for gmail.  If that's the only domain you care about, wonderful.

--keith

-- 
kkeller-usenet@wombat.san-francisco.ca.us
(try just my userid to email me)
AOLSFAQ=http://www.therockgarden.ca/aolsfaq.txt
see X- headers for PGP signature information

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#11206

In comp.os.linux.misc, The Natural Philosopher  <tnp@invalid.invalid> wrote:
> On 06/06/14 18:39, Keith Keller wrote:
>> You will almost certainly not get down to 99:1 with any method that
>> doesn't involve sending mail out with a token, and waiting for the user
> On te contrary test show that testing gmail with a rcpt to: 
> invalid@gmail.com  gets an instant naff off. So it looks like 100% will 
> work.

Just a FYI, when I encounter forms that want some lamely checked "valid"
email address in order for me to contact them about say, broken web
pages, I just plug in email addresses that point back to the same site,
eg for www.not.named.site, use "postmaster@not.named.site" or webmaster@

If no one reads it, well, I can't help that, but use those forms knowing
that no human may be at the other end regardless of what I enter.

Elijah
------
postmaster@gmail.com did not immediately bounce....

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#11231

Eli the Bearded <*@eli.users.panix.com> wrote:
> postmaster@gmail.com did not immediately bounce....

For organisational domains hosted by Google, the postmaster and abuse
addresses are "monitored by Google". It's possible to have copies of
emails to those addresses forwarded to a local address, but it's not
possible to have them disabled.

OTOH, I don't know if such addresses are actually reviewed.

Chris

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#11274

The Natural Philosopher <tnp@invalid.invalid> wrote:
>On te contrary test show that testing gmail with a rcpt to: 
>invalid@gmail.com  gets an instant naff off. So it looks like 100% will 
>work

Do that too often and end up in a local blacklist.

Greetings
Marc
-- 
-------------------------------------- !! No courtesy copies, please !! -----
Marc Haber         |   " Questions are the         | Mailadresse im Header
Mannheim, Germany  |     Beginning of Wisdom "     | http://www.zugschlus.de/
Nordisch by Nature | Lt. Worf, TNG "Rightful Heir" | Fon: *49 621 72739834

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#11169

On 6/4/2014 8:48 PM, The Natural Philosopher wrote:
> I have web contact pages which are used by anyone to send enquiries.
>
> I want to make sure that anyone using them has a valid reply address set
> in a web form BEFORE I forward the message on to the site administrators.
>
>
> Mailer is exim, and that's currently but not necessarily invoked by the
> php mail() function.
>
>
> what I want is a function like
>
> is_valid_mail("user12345@gmail.com")
>
> that will return true or false if gmail accepts the user as known (yes
> the spam is always @gmail.com) WITHOUT having to write a dns mx lookup,
> then connect to socket 25 and etc etc etc..
>
> exim -bt tells me if the domain is valid, but not the user.
>
> I am not particular how its achieved - anything can be merged into the
> existing code.
>
> anyone done this?
>
>

The only way you can do this is to send an email to the address they 
specify and require a response.  While you can determine if a domain 
name is invalid, there is no way to determine whether an email within a 
domain is valid without requiring a response from that email address.

I know you won't see this, but others who might have a similar question 
will.


-- 
==================
Remove the "x" from my email address
Jerry Stuckle
jstucklex@attglobal.net
==================

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#11177

"The Natural Philosopher" <tnp@invalid.invalid> schreef in bericht 
news:lmoeok$5v6$1@news.albasani.net...
> what I want is a function like
>
> is_valid_mail("user12345@gmail.com")
>
> that will return true or false if gmail accepts the user as known (yes the 
> spam is always @gmail.com) WITHOUT having to write a dns mx lookup, then 
> connect to socket 25 and etc etc etc..
>
> exim -bt tells me if the domain is valid, but not the user.
>
> I am not particular how its achieved - anything can be merged into the 
> existing code.

As an idea to work on:

is_valid_mail() checks your database for known users.
If unknown, display a 'verify first' page.
Present a unique code which the user has to mail back to you.
Still not 100% save, but if a user can send using a certain address, there's 
reason to believe he can receive as well. Add the user to your database.

Not enough?
Make it a three way handshake.
The user mails you his code, your autoresponder sends (after verifying the 
code, obviously) another unique code.
Your form checks { is_valid_mail() or presents_valid_code() }
You now have proof email traffic is possible in both directions.

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#11179

On 05/06/14 11:59, AvdB wrote:
> "The Natural Philosopher" <tnp@invalid.invalid> schreef in bericht
> news:lmoeok$5v6$1@news.albasani.net...
>> what I want is a function like
>>
>> is_valid_mail("user12345@gmail.com")
>>
>> that will return true or false if gmail accepts the user as known (yes
>> the spam is always @gmail.com) WITHOUT having to write a dns mx
>> lookup, then connect to socket 25 and etc etc etc..
>>
>> exim -bt tells me if the domain is valid, but not the user.
>>
>> I am not particular how its achieved - anything can be merged into the
>> existing code.
>
> As an idea to work on:
>
> is_valid_mail() checks your database for known users.

There are no known users.

Or hey wouldn't be using the contact page.

> If unknown, display a 'verify first' page.
> Present a unique code which the user has to mail back to you.
> Still not 100% save, but if a user can send using a certain address,
> there's reason to believe he can receive as well. Add the user to your
> database.

Making it bloody awkward for genuine users defeats the purpose.

>
> Not enough?
> Make it a three way handshake.
> The user mails you his code, your autoresponder sends (after verifying
> the code, obviously) another unique code.
> Your form checks { is_valid_mail() or presents_valid_code() }
> You now have proof email traffic is possible in both directions.
>
>
At this point genuine enquirers have simply buggered off elsewhere.

>


-- 
Ineptocracy

(in-ep-toc’-ra-cy) – a system of government where the least capable to 
lead are elected by the least capable of producing, and where the 
members of society least likely to sustain themselves or succeed, are 
rewarded with goods and services paid for by the confiscated wealth of a 
diminishing number of producers.

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#11184

The Natural Philosopher <tnp@invalid.invalid> wrote

> I have web contact pages which are used by anyone to send enquiries.
> 
> I want to make sure that anyone using them has a valid reply address 
set 
> in a web form BEFORE I forward the message on to the site 
administrators.
> 
> 
> Mailer is exim, and that's currently but not necessarily invoked by the 
> php mail() function.
> 
> 
> what I want is a function like
> 
> is_valid_mail("user12345@gmail.com")
> 
> that will return true or false if gmail accepts the user as known (yes 
> the spam is always @gmail.com) WITHOUT having to write a dns mx lookup, 
> then connect to socket 25 and etc etc etc..
> 
> exim -bt tells me if the domain is valid, but not the user.
> 
> I am not particular how its achieved - anything can be merged into the 
> existing code.
> 
> anyone done this?
> 
> 

As others have said, there really is no reliable way to do this, other 
than actually sending an email and waiting for a response.  Groupmail by 
Infacta does have the ability to verify addresses in a list.  It waits 
for a response back and whatever the undeliverable response is, invalid 
domain, invalid user, full mailbox, etc.  This allows you to keep clean 
email lists.

But, that is not going to help you in your application.  I have several 
email addresses, and if I want a response back to something, then I use 
my primary email address.  If it's something I think is going to add me 
to some mailing list, then I use one of the other ones.

So, you could put something on your form like:

"Please use a valid email address.  Your issue will not be addressed if 
our email to you is returned."

-- 
Adrienne Boswell
Arbpen Web Site Design Services - http://www.cavalcade-of-coding.info/
The Good Plate - Fresh Gourmet Recipes - http://the-good-plate.com/
Please respond to the group so others can share

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