steam learn: email deliverability

30th of October 2014

Email deliverabilityHow can my email reach the recipient’s inbox?

by Pierre Cornic


Email deliverability

1. It’s not that easy

2. Deal with bounces

3. Avoid SPAM filters

4. Great tools to help you


1- It’s not that easy

“(...) It is important to note that just because the mail was accepted for delivery, it does NOT mean the mail will actually reach the intended destination.”

http://fr.php.net/mail

Is calling <?php mail(); ?> enough?


1- It’s not that easy

Bounces

● Wrong email address● Recipient mailbox full● Mail server unavailable

What could go wrong ?

SPAM

● SPAM folder● Blocked by ISP


2- Deal with bounces

➢ Hard bounce○ Permanent rejection○ For example “Mailbox does not exist”

➢ Soft bounce○ Mail server temporarily unavailable to receive○ Automated retry○ Can lead to hard bounce

2 types of bounces



● Bounces (soft and hard) impact your IP/domain reputation.

● Sender IP or domain may be blocked.

Why it does matter?

Acceptable bounce rate is below 2%!



● Stop sending to these addresses○ Create mailbox for bounce notification○ Periodically retrieve them and update emails

● Validate emails at subscription

● Do not buy lists or use crawlers to find emails

Reduce bounce rate


3- Avoid SPAM filters

● No unified policy across ISP● SPAM rules evolve over time● Your IP/domain reputation changes

When will my email go to SPAM?

A. Validate sender identityB. Write a good email contentC. Inform the recipient and provide easy opt out

Best practices



What is it?● Indicates who can send email for a domain● Published DNS TXT record

Use it!➢ Check your domain: http://mxtoolbox.com/spf.aspx➢ Build your SPF : http://www.spfwizard.net/

A. Validate sender identity with SPF

SPF = Sender Policy Framework

http://mxtoolbox.com/spf.aspx


SPF : Sender Policy Framework



What is it?● Private key on mail server, public key in DNS● Adds a signature to your email header● Validates content and origin● Removes ”sent via” header

A. Validate sender identity with DKIM

DKIM = Domain Keys Identified Mail



What is it?● Private key on mail server, public key in DNS● Adds a signature to your email header● Validates content and origin● Removes ”sent via” header

Use it!➢ Generate public/private key: http://www.socketlabs.com/domainkey-

dkim-generation-wizard/➢ Publish 2 DNS TXT records


http://www.socketlabs.com/domainkey-dkim-generation-wizard/





Policy record:_domainkey.inovia.fr IN TXT o=~;

Key record(s):test._domainkey.inovia.fr IN TXT k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDTCSGHCtKkd+Kwj30llDAiZ0JvU2M+ZZD3YQRA6EEQgCzwd/XDJp9etuoIn7Am7p4wZYn13N35ebu1X/ul5z6O/DyY5SaoNsVr+b79UesrzgRXwwDaWbsKnbmDQJmuU8kVdhiYhIzbbcf8Xz6L5pbe1rWhfMYivGGpcL94GmM9GQIDAQAB


Use it!






Best practices



B. Write a good email content

Guidelines● Short subject (35 to 50 characters)● No spammy words (free, sale, cash, etc.)● Avoid CAPITALIZED LETTERS● Not too much images● Good spelling and no HTML errors● Avoid using too much bold, red font, !, ?, €






Best practices



In short: “Please, please, don’t click on the little “SPAM” button !”

Guidelines● Remind the recipient why he receives your email● Tell him who you are (address of company is mandatory in your

email)● Provide him a simple unsubscribe link

C. Inform recipient and provide easy opt out


Marketing email

● Bulk emails● Sent to a list of people● Promotions, new products, etc.

4- Great tools to help you

Transactional email

● One to one email● Results of a user action● For example: password reset,

order confirmation

Different types of emails, different tools



Transactional email services

● Mandrill (free up to 12 000 emails/month)

● Sendgrid (free up to 200 emails/day)

● Postmark (25000 first emails free)

● Mailjet (free up to 12 000 emails/month)

● Customer.io (free up to 200 email contacts)

Provide DKIM, unsubscribe, bounce, open and click tracking.



Marketing email services

● Mailchimp (free up to 2 000 subscribers)

● Mailjet (free up to 12 000 emails/month)

● Vertical response (free up to 1000 subscribers)

● Customer.io (free up to 200 email contacts)

Provide DKIM, unsubscribe, bounce, open and click tracking.


➢ It’s not that easy

➢ You have to deal with bounces

➢ You shall avoid SPAM filters

➢ And now you have great tools for that !

➢ And you know why it matters

Conclusion


Questions ?For online questions, please leave a comment on the article.


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steam learn: email deliverability

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