Delivery Errors

Delivery errors are issues that arise when a business or individual attempts to send emails to recipients. They can occur due to invalid or inactive email addresses or problems with email servers.

In this article, we’ll unveil why you should monitor email delivery errors, uncover the types, and show ways to avoid them. We’ll also explain how to improve email deliverability.

Why should you monitor email delivery errors?

Email delivery errors can negatively affect email marketing campaigns by reducing deliverability rates, damaging the sender’s reputation, and impacting engagement metrics like open rates and click-through rates. That’s why we recommend that you monitor email delivery errors, which will help you improve in the following areas.

• Identify technical problems promptly. Email delivery errors often indicate issues with your email server. By tracking these issues, you can resolve them quickly, protecting your sender reputation, email deliverability, and open and click-through rates.
• Optimize email campaigns’ performance. Monitoring delivery errors allows you to identify outdated and invalid email addresses, which is essential for making your campaigns even more effective. Additionally, it helps you remove inappropriate email content or specific elements that cause your emails to end up in spam folders. Removing these triggers will help your campaigns reach subscribers’ inboxes and encourage the necessary actions.
• Comply with regulations. You can ensure compliance with GDPR and CAN-SPAM. Sometimes, you need to remove inactive or invalid email addresses from your mailing lists or improve your opt-out options to meet the requirements. Monitoring is essential for audits and regulatory compliance. Resolving delivery issues positively influences deliverability, resulting in emails reaching subscribers’ inboxes faster. These emails become more visible to people, making them more likely to notice and open them, leading to higher email open rates. а
• Increase click-through rates. Besides improving open rates, you can also encourage more people to click through your email campaigns. Solving delivery issues promptly enables you to maintain a positive sender reputation and avoid being blacklisted. When email services see that you are a reliable sender, they allow you to deliver email campaigns directly to subscribers’ inboxes without being marked as promotions or spam. As a result, they become more visible and likely to be clicked through.
• Get a better sender reputation. Improve your sender reputation. Sending emails to invalid or inactive addresses, experiencing deliverability issues, and frequently landing in spam folders can damage your sender's reputation. This harms your domain’s sender score, increasing the likelihood of future campaigns being marked as spam. By regularly monitoring and addressing potential issues, you can prevent your IP from being blacklisted.

Now that you have some significant reasons to track your email delivery errors, let’s explore their top types and ways to avoid them.

6 Email Delivery Errors and How to Avoid Them

Email delivery errors occur when your campaigns fail to reach recipients' inboxes for various reasons. By understanding the most common errors, you can prevent them and maximize the effectiveness of your email campaigns. Let’s dive in.

• Invalid email addresses. Failing to regularly clean your mailing list can lead to invalid or inactive addresses, preventing email campaigns from reaching recipients. To avoid this, routinely clean your list and validate new addresses before adding them. Email verification tools can quickly identify invalid addresses, often within seconds. Many email marketing platforms, like SendPulse, offer built-in validation to streamline this process.
• Blocked by spam filters. Sometimes, specific content, formatting, subject lines, or sender reputation in your email campaigns can trigger spam filters. As a result, emails end up in spam folders without being noticed by recipients. If you want to avoid such a scenario, it’s necessary to authenticate emails using SPF, DKIM, and DMARC records, send emails through a reliable email service provider, and prevent including keywords that activate spam filters.
• Negative sender reputation. Delivering email campaigns to inactive email addresses carries a negative impact on your domain or IP reputation. It causes problems with email deliverability. However, you can avoid such issues by watching your sender’s reputation. Consider using special tools like SenderScore, TrustedSource, or BarracudaCentral. Once you identify issues, pay close attention to invalid addresses and email elements that harm your reputation. Eliminate them as soon as possible.
• Blacklisting. Repeated delivery problems, such as spam complaints or invalid email addresses, can harm your sender IP and damage your domain reputation, leading to blacklisting. To prevent this, follow proper email marketing strategies and monitor blacklists so you can quickly address any issues.
• Attachment problems. Sending large or prohibited attachments can cause email servers to reject your messages, preventing delivery. To avoid this, compress large files or use dedicated platforms to share attachments. Additionally, ensure that the files comply with server policies for seamless delivery.
• Hard and soft bounces. Sending emails to invalid or inactive addresses causes hard bounces, while temporary issues like server downtime lead to soft bounces. To address hard bounces, remove invalid or inactive email addresses from your mailing list.

Now that you know about various types of email errors and how to avoid them, it’s time to proceed to the tips that contribute to better email deliverability.

9 Tips for Long-Term Email Deliverability

While delivery errors can challenge any business, the key is knowing how to resolve them. Along with a structured approach and thoughtful strategies, some effective tips can help. Check them out below.

1. Use double opt-in. To keep your email lists clean, you should send confirmation emails to your new subscribers. The verification links allow you to ensure that the email addresses are valid and active. This also proves that recipients are eager to receive your emails and engage with your content, meaning they aren’t likely to report your sender IP.
2. Clean up your mailing lists. Review your lists regularly to identify inactive or unengaged recipients. Use email address validators to quickly spot and remove invalid or inactive addresses, ensuring better deliverability.
3. Authenticate your emails. Before sending email campaigns, you should authenticate your IP and messages. SPF, DKIM, and DMARC protocols enable you to show recipients that emails come from reliable sources, ensuring that these messages are legitimate.
4. Take care of your domain and IP. Use special services like Sender Score, BarracudaCentral, and Google Postmaster Tools to get information on your IP score, domain reputation, and spam metrics. These tools will help you identify issues with your reputation and promptly solve them without harming your business.
5. Deliver emails on schedule. Consistency is key to maintaining good email deliverability. Stick to a regular sending frequency that your recipients expect. By identifying the optimal day and time for your emails, you can increase visibility and engagement.
6. Provide a visible unsubscribe option. When recipients can’t find an unsubscribe link, they may mark your emails as spam. To protect your sender's reputation and avoid this, make sure every email includes an easily accessible unsubscribe link in the footer.
7. Personalize your emails. Subscribers often mark emails as spam when their content isn’t relevant to their problems, needs, and interests. That’s why it’s crucial to segment your mailing lists and deliver emails based on recipients’ behavior, preferences, and browsing history. By personalizing your email campaigns, you can cater to recipients' needs and prevent them from reporting your sender IP.
8. Optimize your email content to avoid spam filters. Ensure your campaigns don’t contain excessive promotional language, unusual formatting, or suspicious characters, as these can trigger spam filters and prevent delivery.
9. Track your email campaigns’ performance. It’s essential to understand how effective your campaigns are by monitoring engagement metrics. These include open and click-through rates and bounce and complaint rates. They will show you how satisfied recipients are with your email content.

Overall, delivery errors can pose a serious challenge to your email marketing strategy. However, the key is to identify them quickly and take action. By understanding what goes wrong and why your emails aren’t reaching their intended recipients, you can apply our tips to resolve issues swiftly. This will help improve your email deliverability, leading to higher open and click-through rates.

Last Updated: 13.01.2025