Why are people in my mailing list not getting the emails that I am sending out from Certain or getting their confirmation emails once completing their registration?
If an email server filters out a message as spam, typically the email is quarantined and does not reach its destination.
One reason that spam filters block email addressed from an Application Service Provider (ASP), such as Certain, is that the "From" address is not using the same domain as the mail server.
For example, if you customize the "From" to be email@example.com, the email still goes out with Certain's mail server's DNS host name (mail.certain.com) in the header.
To reduce the amount of email quarantined as spam, we modify all email sent form our servers so that the "From" address is always firstname.lastname@example.org and the display name is that of the Registration Contact. The "Reply-To" address will be that of the event's Registration Contact also.
The effect is that email recipients will see the registration contact's name and email address in the "From" field, or the "To" field if they click "Reply". But the receiving mail server will recognize that the email's "From" address is in the same domain as the sending mail server.
The Email "Chain" - a filtering device
When you are logged into Certain and sending an email update to hundreds of attendees, those emails are going through an email “transmission” chain. They pass through a series of mail servers and are subject to scrutiny at several levels:
Certain sends these emails using SendGrid.
Once SendGrid determines the emails are safe to send, their mail servers engage with the recipients' email servers (or email appliance acting in lieu of those servers). This is where another key filtering is taking place:
In a B2B situation, rarely do you directly engage with the end point mail server. You will most likely deal with an appliance that will scan for malware, check for blacklisting, scan content, apply whitelisting settings, and eventually make the determination of letting the email through to the endpoint mail server (or not). In many B2B situations, you are also facing an additional hurdle in terms of client-side filters, such as Outlook’s Junk folder, which will have its own personalized criteria and threshold for keeping email out of the primary inbox.
In a B2C situation, the top 5 ISPs will cover about 80% of your mailing addresses. ISPs have their own filtering systems with requirements that are different in the sense that they are designed to push back on massive amounts of SPAM, in the order of hundreds of billions of emails in a year.
Based on the quick breakdown above, you can see that there are many opportunities for your emails to:
- not be sent
- not be accepted
- be accepted but placed the in the SPAM or JUNK folder
How do you control this?
There are several aspects of your email communication that will affect how your emails are delivered. Some are technical in essence and are designed to authenticate the mail you send through Certain. For the rest, it really is about best practices.
SPF records and Domain Keys are tools that are designed to prove the email that was sent through Certain is coming from a valid source. Since SendGrid will use an IP address that is different from that tied to your domain, establishing that record will ensure mail servers will take the incoming emails as legitimate. Please contact Certain Support to receive an updated SendGrid Authentication email. This email will include a list of records that will need to be added to your DNS host and help then improve deliverability by showing inbox providers that you own the domain.
Know your own environment
As you send test emails to yourself through Certain, you need to know whether your own mail server uses a SPAM firewall. If you do not get your test email, this is the first location you need to check, as SPAM firewalls are keeping track of the emails they bounce. Testing with a regular ISP email address is also a good idea, as it will allow you to establish a baseline of what another mail server accepts (or does not).
Follow best practices
While this may sound obvious, there are many soft rules that apply to email communication best practices. With all the different email filters in place, insignificant mistakes, such as having an email subject that is too long, may prevent you from delivering to a few mail servers, while still having good delivery for others. The rule is simple: If your emails are delivered to some addresses and not others, it has to do with your content and practices.