Email deliverability is multi-faceted and can be complex. When having deliverability issues, the problem may not be apparent. One minor issue can cause problems down the line. This article will provide answers on the more common deliverability issues.
The following user roles can create and send emails:
- Marketing Managers
- Sender Permissions
- Shared and Dedicated IP Addresses
- IP Warming
- Authentication and Blacklists
- Ready to Learn More?
Permission is the most important aspect of deliverability. Senders must have permission to email recipients. When reviewing permissions, review how leads were signed up, and how lists were acquired. To that end, SharpSpring advises to send to recipients who have expressly opted-in. SharpSpring does not permit senders to use purchased, rented, scraped, or stolen lists. Practicing proactive list management also helps maintain permission status.
Additionally, consider if the sender has a permission reminder. Permission reminders are short text blocks, often found at the bottom of the email, that clarifies to subscribers how they were signed up to receive the email.
Shared and Dedicated IP Addresses
All email, regardless of content or origination, is sent over an Internet protocol (IP) address. A collection of IP addresses are called pools. The type of IP address may impact deliverability. For marketing automation, shared and dedicated addresses are used:
- Shared addresses are single IP addresses that are shared by multiple websites on a single server.
- Dedicated addresses are IP addresses that are tied to only one website.
Shared addresses can pose problems with deliverability, as all websites tied to the shared address may be impacted by blacklisting or other issues. In turn, these issues can impact deliverability rates (and therefore reputation). With shared addresses, IP addresses or pools may be tied to another sender with terrible reputation. If those senders are added to a blacklist or are otherwise blocked, all members of the shared address or pool will suffer the same fate. Shared addresses remove individual agency from senders and place them at the mercy of others.
By contrast, dedicated addresses are tied directly to a website or domain. In this, the sender has full control over all sends over the dedicated address. This places full responsibility with the dedicated sender. Additionally, this isolation serves to protect senders from outside influences and consequences. Consider also that, in being tied to a single website, a dedicated address becomes another aspect of a sender's brand identity. This identity reinforcement can help to build trust with recipients when sending emails.
When deliverability is an issue, blame with these types of addresses usually comes down to the following:
Ultimately, senders are responsible for deliverability. The onus is on senders to prepare and send quality email. IP addresses are a part of this.
Note: SharpSpring senders are, by default, set to use shared IP pools. However, you may request a dedicated IP address at any time. For more information, contact
Deliverability may also hinge on whether or not an IP address has been properly warmed. IP warming is where senders gradually send more and more emails over an address or pool.
If an IP address comes into existence (or is used after an extended period of inactivity) and immediately begins sending a massive volume of emails, Internet service providers (ISPs) take notice. As overall volume is taken into account when ISPs consider if IP addresses and pools are spam addresses, it is imperative to begin warming these otherwise cold addresses.
Note: For more information regarding SharpSpring IP warming metrics, contact
Authentication and Blacklists
Authentication plays a significant role in email deliverability. Unauthenticated emails will not be accepted by most major email providers, such as Gmail. Ensuring emails are authenticated is especially important. There are several factors that impact authentication, and if senders cannot send emails—especially those who previously were able to successfully send—then determining authentication status is paramount.
First and foremost, authentication requires the sender to have SPF and DKIM set up. SharpSpring is a firm believer in this. As of February 2018, all SharpSpring accounts that have not set up DKIM are set as limited from sending emails until DKIM is set up and configured. DKIM, as email authentication, broadcast to recipient Mail Transfer Agents (MTAs) that SharpSpring is permitted to send your mail, and to also aid deliverability.
Even if emails are authenticated, IP addresses or pools may be impacted by poor reputation. Shared IP pools are especially at risk, as one sender can make things difficult for all others sending from the pool. If reputations are poor enough, entire IP pools or domains may be blocked from sending emails. It is imperative that senders maintain good email reputation.
Additionally, links in the emails—or even the emails themselves—may be part of a blacklist. Blacklists are third-party data sources that inform receiving email servers whether the sender or the email content should be considered as spam. While these third parties do not actually block email, email servers may choose to accept or reject the recommendations from blacklists.
It is important to test emails to see if these emails are unauthenticated, blacklisted or otherwise impacted. SharpSpring recommends using MxToolBox. MxToolBox checks to see if CNAME records are properly set up and configured, whether or not emails have blacklisted content, and the overall sending domain status. Testing can only serve to benefit your sends.