Alternative to PHP mail (reason: spam)?

Question

I've had this huge problem with the mails sent from my domain, that are being caught by Gmail's spam-filter. The mails that I'm sending, are invoices to customers who haven't received anything from the sending e-mail address, so I guess that's one reason why the mail is going to spam. I also think that another reason is, that the system sent out about 150 emails before I realized, that they all ended in spam, and according to a MailChimp article, the last row of the first table, then spam-filters notice if the sending-mail have been marked as spam, on other accounts ( the article: http://kb.mailchimp.com/article/avoiding-the-spam-filters ). The system is made in PHP, so I'm trying to make a way, that I can send out e-mails from the system I've made to recipients who haven't received anything from me before - that's all I need to do. It sounds so simple...

Now, I've tried quite a few things. Here are a quick list, so you know what can and can't be done - and what I've tried:

• The domain is hosted with One.com, and they don't support that customers can setup their own SPF-record or DKIM-record (not that I know what they are - because I quickly realized that that wasn't an option to fiddle with that).
• PHPmailer is not an option, since it's hosted with One.com, so I can't install it in the PHP-init-file. So the same goes for the PEAR-mail function (cannot be used).
• I've tried to use PHP's SwiftMailer. Yet, I struggled to change the information in the header, so I stopped trying with that.
• I've looked into using MailChimp's PHP API to send out single e-mails to single recipients (which is what it needs to be able to do). But their API doesn't support that.
• I've considered SendGrid, but I can see that that costs 10 dollars per month, which is kind of expensive, just to be able to send a customer a URL to an invoice... Or that's what I think.
• I've tried to use PHP's mail-function, where I write the header myself. The header can be seen here:

    Delivered-To: [email protected]
    Received: by 10.76.75.104 with SMTP id b8csp48728oaw;
            Sat, 16 Mar 2013 17:32:56 -0700 (PDT)
    X-Received: by 10.152.116.45 with SMTP id jt13mr7897860lab.0.1363480376067;
            Sat, 16 Mar 2013 17:32:56 -0700 (PDT)
    Return-Path: 
    Received: from mail-out2.b-one.net (mail-out2.one.com. [91.198.169.19])
            by mx.google.com with ESMTP id p10si4637427lbb.120.2013.03.16.17.32.55;
            Sat, 16 Mar 2013 17:32:55 -0700 (PDT)
    Received-SPF: neutral (google.com: 91.198.169.19 is neither permitted nor denied by best guess record for domain of [email protected]) client-ip=91.198.169.19;
    Authentication-Results: mx.google.com;
           spf=neutral (google.com: 91.198.169.19 is neither permitted nor denied by best guess record for domain of [email protected]) [email protected]
    Date: Sat, 16 Mar 2013 17:32:55 -0700 (PDT)
    Message-Id: 
    Received: from localhost.localdomain (srv18.one.com [193.202.110.18])
        by mail-out2.b-one.net (Postfix) with ESMTP id F3D0B10365
        for ; Sun, 17 Mar 2013 01:32:53 +0100 (CET)
    Received: from 85.218.159.219 by www.lyobeachcamp.dk via URL_TO_THE_SCRIPT.php with HTTP; Sun, 17 Mar 2013 00:32:53 +0000
    To: RECIEVERS_NAME 
    Subject: Faktura på depositumet
    X-PHP-Originating-Script: 87486:NAME-OF-THE-SCRIPT-THE-E-MAIL-WAS-SENT-FROM.php
    Reply-To: Lyø Beach Camp 
    From: Besked fra Lyø Beach Camp 
    MIME-Version: 1.0
    Sender: Besked fra Lyø Beach Camp 
    Content-type: text/plain; charset="utf-8"; 
    X-Mailer: PHP5.3.21

    Hej E-MAIL-OWNER-NAME. 

    Her er et link til din faktura 

    http://www.lyobeachcamp.dk/ENCRYPTED_URL_TO_INVOICE.pdf . 

    Du skal betale denne faktura indenfor den næste 5 dage. Senere hen vil du modtage en
    faktura på restbeløbet. Du vil så modtage dit rejsebevis kort før afrejse-datoen 
    (omkring to ugers tid før). Vi kan desværre ikke melde de eksate flytider ud, før da. 
    Du kan dog følge med i de midlertidige flytider som vi har på 
    http://www.lyobeachcamp.dk/flytider . 

    Med venlig hilsen 

    Lyø Beach Camp 

    Web: http://www.lyobeachcamp.dk 

    Mail: Hvis der er noget, så er du altid velkommen til at skrive os en mail på 
    [email protected]

So my question is this:

1. Can I either do something really cool that header of mine, to make it pass spam-filters?
2. Is it possible to somehow send the e-mail from a G-mail account or something, from the PHP-system? I mean, if I made a [email protected] or something like that, and was able to send the e-mails automatically (through my PHP-built system), then I guess that would be easier to get to by-pass spam-filters? Or am I dreaming?
3. What other options do I have? All I want, is a way that I can get a URL out to one of my customers? I'm even considering sending bottled message, and throw it in the ocean, since there's a bigger chance that they'll get that, than for them to check their spam-filters for it.

Any points in the right direction, suggestions or thoughts are greatly appreciated. I'm quite desperate here!

Thank you for your time.

Answer 1

Try the Sendgrid system. It is really easy to use and you can use up to 200 sent e-mails per day for free if it is sufficient.

We are using it now in our PHP app and it works nicely.

http://sendgrid.com

Answer 2

If all you had to do was put in a super spiffy header to bypass SPAM filters, don't you think SPAMMERS would do that too? ;)

This isn't a delivery issue. Either A) your IP is blacklisted, or B) your content is spammy. You need an SPF record to really do much more about this issue.

I would absolutely not recommend sending with FROM or REPLY-TO headers from a domain name like gmail.com or something that's very clearly not owned by you.