Issues with imap_mail()

[jokkemokke]

Hi.

I have made a webpage using php which some collegues and I use on my job. Since it is non-work related the webpage is hosted on my private server.

On the webpage there is a number of users which are all registered with their work mail addresses. When a logged in user performs an action on the site, I use the following function call to send mails to the other users:

imap_mail($to_address, $subject, $message, $headers);

Where $to_address is the addresses of the users the mails should be sent to. Depending on how many users I want to send to, I make multible calls to the imap_mail() function.

$headers is set to "Content-type: text/html; charset=iso-8859-1\r\nFrom: $username <$usermail>", where $username is the name of the logged in user and $usermail is the mail address the user is registered with (also his work mail).

Apparently it seems to work fine; when a user performs an action, a mail is send to the work mail address of the other users and the from address is the work mail address of the user that performed the action.

In this way it is possible for the users that receive the mail to press reply and answer the user who performed the action.

The only problem I have is, that if I want to send a mail to many users only some of the mails are received by the users while others are lost. I am guessing that it might be some spam filter on the receive mail server that blocks the mails because the send server does not have the same address as the from mail address in the header.

My question now is if there is some workaround for this. Maybe by doing some modifications to the header to the mail or similar.

Thanks.

[NogDog]

First thing that jumps to my mind is what you may be using for the From header in the additional headers (if you are). If it is not the same as the actual mail account (and server) on the server under which the email is sent, it could be rejected by spam filters. If that's the case, it's better to use a Reply-To header instead.

[jokkemokke]

Yes, I am specifying the reply address in the additional header field with the string "Content-type: text/html; charset=iso-8859-1\r\nFrom: $username <$usermail>". Right now I also tried to modify the code so that I specify the reply address with the rpath field:

$header = "Content-type: text/html; charset=iso-8859-1"
$rpath = "$username <$usermail>"

However, both options seems to give the same at the receive side:

Delivered-To: [e-mail]
Received: by server.work.com
Return-Path: <[e-mail]>
Received: from server.private.com for <[e-mail]>;
From: User 2 <[e-mail]>
To: [e-mail]
Subject: Some Subject
Content-type: text/html; charset=iso-8859-1
Message-Id: <[e-mail]>

I am guessing that the reason the mails are sometime not receive have to do with the "Return-Path:", "Received:" and "Message-Id:" fields, which still contains information about that the mail was send from my private server and not from the work mail server.

Is there some way to modify these fields from the php code also?

I do not have the option to make any changes to my private server except from what I can do from the php code, since it is a hosted webhotel.

[jokkemokke]

I just tried changing the sender mail address to an address own my on domain to see if reason that some mails are not received could be that the sender mail address and the from server do not have the same domain, but it did not help anything.

Could it be that there are some limitation on the server I am sending the mails from? Maybe I am only allowed to send more than a certain amount of mails within a specified time or something?

Is there some way I can check this?

Just for clarification: When I am sending out a large amount of mails, I call imap_mail() multible times, instead of specifying several addresses in the same call. The reason for this is, that the content of the mail varies depending of the receiver.

[dalecosp]

Doesn't imap_mail support additional headers?

Send it an "-f".

$additional_headers = "-f [e-mail]"."\r\n";

Might help...