(PHP Extension) Verify Email Recipients

A way to possibly determine valid/invalid email addresses. I would recommend being very careful about doing this because your IP address may be flagged as a potential spammer by the mail server (because you are probing for valid/invalid email addresses). This Chilkat functionality existed for many years, before this kind of activity became a problem. The functionality remains only because it is useful for some to test with their own SMTP servers.

Chilkat PHP Downloads PHP Extension for Windows, Linux, MacOS, Alpine Linux, Solaris

<?php

// The version number (9_5_0) should match version of the Chilkat extension used, omitting the micro-version number.
// For example, if using Chilkat v9.5.0.48, then include as shown here:
include("chilkat_9_5_0.php");

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

$mailman = new CkMailMan();

// SMTP connection settings...
$mailman->put_SmtpHost('smtp.example.com');
$mailman->put_SmtpUsername('MY_SMTP_USERNAME');
$mailman->put_SmtpPassword('MY_SMTP_PASSWORD');
$mailman->put_SmtpSsl(true);
$mailman->put_SmtpPort(465);

// Create a new email object
$email = new CkEmail();

$email->put_Subject('This is a test');
$email->put_Body('This is a test');
$email->put_From('myemail@example.com');
$success = $email->AddTo('person1','person1@example.com');
$success = $email->AddTo('person2','person2@example.com');
$success = $email->AddTo('person3','person3@example.com');
// The SMTP server smtp.example.com won't know anything about an email address @somewhere_else.com
$success = $email->AddTo('person3','person4@somewhere_else.com');
// ...

// Verify recipients.
// **** See the warning about using this API method in the description above.
// (An SMTP server only knows valid email address for its own domain.  For example,
// smtp.example.com *may* only know if person1@example.com is valid or invalid, but does
// not know anything about the validity of email addresses having other domains.)
$badAddrs = new CkStringArray();
$success = $mailman->VerifyRecips($email,$badAddrs);
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

$i = 0;
while ($i < $badAddrs->get_Count()) {
    print $badAddrs->getString($i) . "\n";
    $i = $i + 1;
}

print 'done.' . "\n";

?>