How do you make sure email you send programmatically is not automatically marked as spam?

Question

This is a tricky one and I've always relied on techniques, such as permission-based emails (i.e. only sending to people you have permission to send to) and not using blatantly spamish terminology.

Of late, some of the emails I send out programmatically have started being shuffled into people's spam folder automatically and I'm wondering what I can do about it.

This is despite the fact that these particular emails are not ones that humans would mark as spam, specifically, they are emails that contain license keys that people have paid good money for, so I don't think they're going to consider them spam

I figure this is a big topic in which I am essentially an ignorant simpleton.

Answer 1

Use email authentication methods, such as SPF, and DKIM to prove that your emails and your domain name belong together, and to prevent spoofing of your domain name. The SPF website includes a wizard to generate the DNS information for your site.

Check your reverse DNS to make sure the IP address of your mail server points to the domain name that you use for sending mail.

Make sure that the IP-address that you're using is not on a blacklist

Make sure that the reply-to address is a valid, existing address.

Use the full, real name of the addressee in the To field, not just the email-address (e.g. "John Smith" <[email protected]> ).

Monitor your abuse accounts, such as [email protected] and [email protected]. That means - make sure that these accounts exist, read what's sent to them, and act on complaints.

Finally, make it really easy to unsubscribe. Otherwise, your users will unsubscribe by pressing the spam button, and that will affect your reputation.

That said, getting Hotmail to accept your emails remains a black art.

Answer 2

A few bullet points from a previous answer:

• Most important: Does the sender address ("From") belong to a domain that runs on the server you send the E-Mail from? If not, make it so. Never use sender addresses like [email protected]. User reply-to if you need replies to arrive at a different address.

• Is your server on a blacklist (e.g. check IP on spamhaus.org)? This is a possibility when you're on shared hosting when neighbours behave badly.

• Are mails filtered by a spam filter? Open an account with a freemailer that has a spam folder and find out. Also, try sending mail to an address without any spam filtering at all.

• Do you possibly need the fifth parameter "-f" of mail() to add a sender address? (See mail() command in the PHP manual)

• If you have access to log files, check those, of course.

• Do you check the "from:" address for possible bounce mails ("Returned to sender")? You can also set up a separate "errors-to" address.

Answer 3

Sign up for an account on as many major email providers as possible (gmail/yahoo/hotmail/aol/etc). If you make changes to your emails, either major rewording, changes to the code that sends the emails, changes to your email servers, etc, make sure to send test messages to all your accounts and verify that they are not being marked as spam.