Email List Health:12 Email Threats Hiding in Your Email List



Halloween is a few weeks away, and trailing just behind is the biggest time of the year for email marketers, the holiday season. We had enough uncertainty this year, don’t let your email lists spook you.

It's important to maintain your email list health throughout the year, but it’s even more critical to clean your lists before you send out your holiday campaigns.  

Test your list with multiple providers to understand which service will best identify the threats in your email lists.

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12 Threats in Your Email Lists that Harm Your Reputation and Deliverability:


1. Disposable Domain

Disposable domains or addresses, sometimes also referred to as throwaway emails, are like burner accounts. They are free email addresses created by people who sign up and double opt-in just for your discount code or coupon. 

At first glance, they look like the perfect customer because they are real people going through your process of offering personal information to get your incentive or offer. In the end, a disposable email only has a lifespan of minutes, hours, or days. Then, like a time bomb, poof, it's gone, and you’re left sending to an email address that no one engages with. 

Even worse, disposable domains are a huge privacy issue because when these are created, they are connected to a public inbox. If that email was used to change a password or if it contains payment information, medication information, or other sensitive information, it’s now visible to the public.

2. Zombies

At Webbula, we refer to emails that belong to deceased individuals as Zombie accounts. The email was once real, but now that no one is behind it, you will not see engagement. Internet service providers (ISPs) rely on engagement. If there is none, it could hurt your sender reputation and waste time and resources. 

Because zombies once had a user, they will pass a verification cleanse. Only Webbula Email Hygiene can detect Zombies. Because we link personal identifying information at the individual level, we receive monthly reports with updates to any individual's PII data, including if the person who owns the email address has passed. 

3. Bots

Bots are designed to locate sign-up forms on the web and submit fake email addresses, subscribing to your email. The cumulative effect of fraudulent sign-ups will negatively impact your sender reputation, open, click, and conversion rates. 

Bots can open and click through your emails, bypassing your double opt-in. The only accurate way of identifying bots in your email list is through an email list hygiene cleanse after the data capture.

4. Phishing Emails

Phishing emails are a type of phishing attack where the invader uses social engineering to try and “hack the human” to get access to valuable information, such as usernames, passwords, or credit card numbers.

You might be wondering, how does this affect me as an email marketer? You’re guilty by association. As with any dead-end email, phishing email addresses will damage your email engagement rates.  Utilize Email Hygiene to identify phishing emails and to protect you from being blocklisted.

5. Spam Traps

Spam traps are created and monitored by blocklist firms and anti-spam organizations to catch malicious senders. There are eight types of spam traps, including recycled, pristine, honeypots, message-IDs, and many more. 

Sending to a spam trap can cause a domino effect. When an email isn’t needed anymore, the inbox provider will shut off the email after a certain period.

Suppose a marketer sends to an inactive email address. In that case, the inbox provider will return a hard bounce, which tells the sender to remove the email address from their list, and most do. However, unfortunately, we still have email marketers who ignore it, a grave mistake. Ignoring spam traps will result in blocklistings and a damaged sender reputation, both of which are bad for business.

Avoid sending to spam traps by cleaning your list with Email Hygiene. Verification checks can detect typo traps, but they cannot detect pristine traps or even honeypots because these types of spam traps are active email addresses. 

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6. Malicious Moles

Think of moles as the undercover cops of email. Moles are real people that sit behind emails. They anonymously report the campaign stats to the cops, AKA real-time blocklists.

Verification effectively mitigates the risk of inactive email addresses within your lists, but it has no impact on the harmful active email addresses such as moles. There are real people who open your emails.

7. Seeded Trackers

Seeded trackers are used to track delivery rates within your marketing campaigns. There is also nothing wrong with them besides the fact that someone is tracking your activity.  

8. Screamers

Screamers are the next-level complainers who look forward to reporting you to ISPs, the FTC, or blocklists. Enough complaints, you’ll be monitored and potentially be placed on a list.

Webbula Email Hygiene can detect screamers over simple verification because we track an email from its creation, use, deletion, and reactivation as a recycled bounce.

9. Blocklisted Emails

These are email addresses that belong to organizations, associations, or networks that have been reported for spam and for which email delivery is blocked. Email can no longer be sent or received at that account after being blocklisted. 

Additionally, customer data degrades over time, causing bounces, complaints, greylisting and more, resulting in low sender reputation and potential blocklisting. Because spam traps deliver, open, and click, it is essential to protect your email marketing resources with regular Email Hygiene cleaning.

10. Shadow Domains

Shadow domains are emails from domains that are rented and shared for bot invasions. You’ll typically see nefarious individuals or companies running scams or intentionally attacking a network or website from shadow domains so it can’t be traced back to them. 

To avoid these attacks on you and your company, it’s best to identify if you have shadow domains in your lists with email hygiene.

11. Greylisting

Greylisting requires the sender to take an extra step to verify that they aren’t a spammer. Think of it as an autoresponder to prove that a sender is a real person. 

The reason why greylisting is effective is due to the number of mass email tools used by spammers that will most likely not retry to send another email after the first delivery failure message. So the spam message never gets delivered to the inbox. 

Why should email marketers care?

Suppose the spammer does try to deliver the message again and waits to send after the expiration date. In that case, this will help any automated spam trap have a good chance of identifying the spam’s source and submitting it to a particular message in their database. With all of these attempts happening, they are more likely to be detected as spam from others than they were before the greylisting delay process.

12. Duplicates

Duplicate emails are exactly what they sound like, the same email delivered more than once to the same subscriber. No one wants the same email in their database twice. Avoid duplicates and run your email lists through email verification.


In Conclusion

The more you understand the threats in your email lists, the more likely it is that you'll take the proper measures to improve your email list health, while growing your email list. Relying on simple verification leaves your email lists exposed to the threats listed above that could negatively impact your email campaigns and your business.

If you want to identify these threats, Email Hygiene allows you to take a step further than simple verification and protect your marketing assets such as web forms, brand reputation, sender reputation, data acquisitions, and marketing campaigns.

About the Author

Jenna Devinney

Jenna Devinney, Marketing Specialist 

Jenna Devinney is the Marketing and Communications Specialist at Webbula. She manages social media, creates eye-catching content, and oversees web design. She’s a jill of all trades writing a surplus of 100+ blog articles over two and a half years in the email hygiene and data solutions space. 


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