Email Deliverability

1. What we did

We at Eventboost are strongly committed to email deliverability issues and implemented every authentication method available in order to ensure that email messages sent from our platform would be correctly delivered to the recipients’ inbox: SPF, SenderID, DKIM and DMARC.
In addition, we developed “safe” email templates, checked and validated against the major spam filters in relation to every content, design, coding, and technical aspects that can interfere with a regular delivery.
These email templates have been optimized for 50+ email clients (desktop, tablet, smartphone, and web), so you can be sure that your email will be displayed correctly on every fixed or mobile device.

2. Email Authentication

Email authentication is used by more and more service providers. In Hotmail, for example, messages that cannot be verified with either SenderID or SPF are flagged with a question mark icon. gMail is already checking the SPF records and noting whether the test passed or not in the header of the message. More and more ISPs will use email authentication as an additional way to discriminate between SPAM and valid email messages. Based on the above, you can see why implementing these methods is and will be more and more important to ensure that your messages are delivered, and delivered to the Inbox.
Sender Policy Framework (SPF)
Sender Policy Framework (SPF) is a simple email-validation system designed to detect email spoofing by providing a mechanism to allow receiving mail exchangers to check that incoming mail from a domain comes from a host authorized by that domain's administrators. The list of authorized sending hosts for a domain is published in the Domain Name System (DNS) records for that domain in the form of a specially formatted TXT record. Email spam and phishing often use forged sender-addresses, so publishing and checking SPF records can be considered anti-spam techniques.
The SenderID Framework is a protocol created by Microsoft to counter email domain spoofing and to provide greater protection against phishing schemes by verifying an email message's sender. Sender ID is heavily based on SPF, with only a few additions. Sender ID tries to improve on a principal deficiency in SPF: that SPF does not verify the header addresses that indicates the sending party. Such header addresses are typically displayed to the user and are used to reply to emails. Indeed such header addresses can be different from the address that SPF tries to verify; that is, SPF verifies only the "MAIL FROM" address, also called the envelope sender.
DomainKeys Identified Mail (DKIM) Signatures
DomainKeys Identified Mail (DKIM) is an email validation system designed to detect email spoofing by providing a mechanism to allow receiving mail exchangers to check that incoming mail from a domain is authorized by that domain's administrators and that the email (including attachments) has not been modified during transport. A digital signature included with the message can be validated by the recipient using the signer's public key published in the DNS. In technical terms, DKIM is a technique to authorize the domain name which is associated with a message through cryptographic authentication.
Domain-based Message Authentication, Reporting and Conformance (DMARC)
Backed by some very large corporations, including Google, American Greetings, PayPal, Microsoft and FaceBook, just to name a few, DMARC, or Domain-based Message Authentication, Reporting & Conformance, is an approach at stopping or reducing email spam and phishing attacks. It expands on two existing mechanisms, the well-known Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM), coordinating their results on the alignment of the domain in the From: header field, which is often visible to end users. It allows specification of policies (the procedures for handling incoming mail based on the combined results) and provides for reporting of actions performed under those policies.

All the above authentication methods have been tested and validated using a lot of different tools, like Unlock the Inbox, Port25 Email Verifier, Dmarcian, Litmus, ORF Fusion SPF Policy Tester, Message System Validator,, MxToolbox, etc. You can check validation results of our sample templates here:
Unlock the Inbox
Invitation Email
• Confirmation Email
Port25 Email Verifier
Invitation Email
Confirmation Email

3. Spam Check

Email spam, also known as junk email or unsolicited bulk email (UBE), is the practice of sending unwanted, irrelevant email messages, frequently with commercial content, in large quantities to an indiscriminate set of recipients.
Spam filters consider a long list of criteria when judging the “spamminess” of an email. They’ll weigh each factor and add them up to determine a spam score, which then determines whether an email will pass through the filter. If your email’s total “spam score” exceeds a certain threshold, then your email goes to the junk folder. Passing scores are determined by individual server administrators, so unfortunately, what passes some filters doesn't pass all of them. In addition, spam filters don’t publish their filtering practices, as doing so would give spammers the knowledge needed to bypass filters and harm their users.
But before an email even gets to that filter, it first has to pass through a gatekeeper or "firewall." Firewalls are used by ISPs, large corporations, and small businesses alike, and they all communicate with each other to help identify spam and spammers.
If a firewall thinks your email is spam, it will reject it before your recipient’s spam filter even has a chance to see it. It won’t even waste the energy to tell anybody about it, which means it won't appear on a bounce report.

You can find below a list of common mistakes that can result in spam filtering:
Using phrases like “Click here!” or “Once in a lifetime opportunity!”
• Excessive use of exclamation points!!!!!!!!!
• Using bright red or green colored fonts.
• Using bad content. This one’s broad, but important. Email delivery expert Laura Atkins details content-based filtering in this article.
• Coding sloppy HTML, usually from converting a Microsoft Word file to HTML.
• Creating an HTML email that’s nothing but one big image, with little or no text. Spam filters can’t read images, so they assume you’re a spammer trying to trick them.
• Using the word “test” in the subject line. Agencies can run into this issue when sending drafts to clients for approval.
• Sending a test to multiple recipients within the same company. That company’s email firewall often assumes it’s a spam attack.

All email templates available in the Eventboost platform have been validated against the major spam filters and checked against content, design and technical aspects.

You can check validation results of our sample templates here:
Confirmation email

4. Email Client Optimization

Due to the lack of standards for rendering HTML & CSS within the various email clients, email coding is a key point to guarantee your messages will look great on every desktop, web, tablet and smartphone client.
Our “safe” email templates have been deeply optimized in order to look the same on the majority of desktop and web email clients. On top of that, we also developed a mobile template since 53% of people read email on their mobile devices.

Our templates have been tested and validated for 50+ different email clients. You can check validation results of our sample templates here:
Confirmation email

5. What should I do?

If you want to give your emails the highest chance of being delivered to your guests, you should implement SPF, SenderID and DKIM authentication on the domain you are using in the From field of your email messages (yourdomain) sent by the Eventboost platform: invitation, confirmation, and other messages.

SPF and SenderID
You should add this TXT record in the DNS of yourdomain, in order to authorize our mail sender service to send emails on your behalf.:
"v=spf1 ~all"
If an SPF record already exists, please update it adding

You should create a new DNS record in yourdomain with a digital signature provided by Eventboost.
Eventboost will send you the exact record you have to create and, when you’ve done, simply let us know so we can complete the DKIM configuration on our servers.

6. Conclusions

Once point 5 has been correctly implemented, the chance for your emails of being filtered by a firewall or going into the recipient spam folder will be really low. Authentication methods have been implemented and tested, our email templates have been checked and validated, every aspect of email deliverability has been taken into consideration.

Nevertheless, we can’t promise that all your emails will be correctly delivered, because you could have modified the email template in a way that some mailservers consider it SPAM (adding stop words, leaving only a big image without text, using text or links that have the same color as the background, etc.), or because of extremely high security settings of some large companies that prevent your message to be delivered.
If this is the case please contact Eventboost, and our technical staff will be happy to provide assistance.