PHPMailer setting for individual emails is sending empty To: fields - php

Question

Using PHPMailer to send individual emails to recipients I'm getting nothing in the To: field when I add $mail->SingleTo = TRUE; to my code.
When I remove $mail->SingleTo = TRUE; I receive emails with an email address in the To: field that is correct.
This is what I get:
reply-to xxxxxx <xxxx#xxxx.com>, No Reply <no-reply#no-reply.com>
to
date Mon, Mar 21, 2011 at 5:07 PM
subject Testing
mailed-by gmail.com
signed-by gmail.com
(where xxxxxxx represents my email address.)
Here's my code:
if(isset($_POST['submit']))
{
require_once('PHPMailer_v5.1/class.phpmailer.php');
$mail = new PHPMailer();
$subject = $_POST['subject'];
$body = $_POST['emailbody'];
$to = $_POST['to'];
$mail->IsSMTP(); // telling the class to use SMTP
//$mail->Host = "localhost"; // SMTP server
$mail->SMTPDebug = 2; // enables SMTP debug information (for testing)
// 1 = errors and messages
// 2 = messages only
$mail->SMTPAuth = true; // enable SMTP authentication
$mail->SMTPSecure = "SSL"; // sets the prefix to the servier
$mail->Host = "smtp.gmail.com"; // sets GMAIL as the SMTP server
$mail->Port = 587; // set the SMTP port for the GMAIL server
$mail->Username = "xxxxxxxxxx#gmail.com"; // GMAIL username
$mail->Password = "*********"; // GMAIL password
$mail->SetFrom('xxx#xxx.com', 'XXXXXX');
$mail->AddReplyTo("no-reply#xxxxx.com","No Reply");
$mail->Subject = $subject;
// After adding this line I'm getting an empty To: field
$mail->SingleTo = TRUE;
$mail->AddAddress("address1#xxxxxx.com", 'xyz abc');
$mail->AddAddress("address2#xxxxxx.com", 'abc xyz');
//$mail->AltBody = "To view the message, please use an HTML compatible email viewer!"; // optional, comment out and test
$mail->MsgHTML($body);
if(!$mail->Send()) {
$message= "Mailer Error: " . $mail->ErrorInfo;
}
else
{
$message= "Message sent!";
}
}

Answer 1

You are using SMTP to send email. The phpmailer class is not using the SingleTo parameter when senting using Smtp.
More, if you see the CreateHeader function when the SingleTo == true the recipents are only aded to $this->SingleToArray and not to the header itself so basically it PHPmailer bug.
Looks like the only choice, unless you want to patch phpmailer, is to send email one-by-one without using SingleTo property
the solution will be
function & prepare_mailer($subject, $body) {
$mail = new PHPMailer();
$mail->IsSMTP(); // telling the class to use SMTP
//$mail->Host = "localhost"; // SMTP server
$mail->SMTPDebug = 2; // enables SMTP debug information (for testing)
// 1 = errors and messages
// 2 = messages only
$mail->SMTPAuth = true; // enable SMTP authentication
$mail->SMTPSecure = "SSL"; // sets the prefix to the servier
$mail->Host = "smtp.gmail.com"; // sets GMAIL as the SMTP server
$mail->Port = 587; // set the SMTP port for the GMAIL server
$mail->Username = "xxxxxxxxxx#gmail.com"; // GMAIL username
$mail->Password = "*********"; // GMAIL password
$mail->SetFrom('xxx#xxx.com', 'XXXXXX');
$mail->AddReplyTo("no-reply#xxxxx.com","No Reply");
$mail->Subject = $subject;
$mail->MsgHTML($body);
return $mail;
}
foreach( $_POST['to'] as $to ){
$mail = null;
$mail = & prepare_mailer($_POST['subject'],$_POST['body']);
$mail->AddAddress($to['address'], $to['name']);
$mail->Send();
}

Answer 2

Set up all the other parameters, then in a loop set the recipient, send the email, then use the ClearAllRecipients() function. Like so:
{ // loop start
$mail->AddAddress($person_email, $person_name);
$mail->Send();
$mail->ClearAllRecipients();
} // loop end

Answer 3

The problem is in the SmtpSend function (starting at line 701 in class.phpmailer.php). As you can see there, they don't take the singleTo setting into account, and just add all recipients and send the body of the message once.
So you should add some logic there to test if singleTo is true, and if it is modify the code so it sends these mails separately, prefixing the To: header to the body of the message. If singleTo is false you can call the code as-is (line 713 - 758).
Or alternatively, if you don't want to patch things, then you could use a transport method (ie. sendmail) that does seem to support the singleTo parameter.

Answer 4

$mail->AddAddress()
doesn't like CSV's
so if you have:
$Emails="addr1#host.com,addr2#host.net"; #etc;
do a for loop after a split:
$NewList = preg_split("/,/",$Emails);
foreach ($NewList as $k=>$email){
if ($k==0) $mail->AddAddress($email); # Add main to the "To" list.
else $mail->AddCC($email); # The REST to CC or BCC which ever you prefer.
}
-- BF.

Answer 5

SingleTo Is not a good idea. It only works with "sendmail" or "mail" transports, not with SMTP. If you use SingleTo with SMTP, this parameter is just ignored without any error or warning, and you may get duplicates.
Since you use both SingleTo an SMTP, as shown in your code, the SingleTo in your case is ignored.
The SMTP protocol is designed in a way that you cannot send one message to several different recipients, each having only its own address in the TO: field. To have each recipient have only its name in the TO:, the whole message have to be transmitted again. This explains why SingleTo is incompatible with SMTP.
According to the authors of the PHPMailer library, SingleTo is planned to be deprecated in the release of PHPMailer 6.0, and removed in 7.0. The authors have explained that it's better to control sending to multiple recipients at a higher level, since PHPMailer isn't a mailing list sender. They tell that the use of the PHP mail() function needs to be discouraged because it's extremely difficult to use safely; SMTP is faster, safer, and gives more control and feedback. And since SMTP is incompatible with SingleTo, the authors of PHPMailer will remove SingleTo, not SMTP.