The complete guide to troubleshooting email deliverability issues
Inna Sabada
by Inna Sabada
The complete guide to troubleshooting email deliverability issues

When it comes to sending a large volume of emails, email deliverability issues can crop up very quickly and unexpectedly. Even if you did well yesterday, your deliverability can drop dramatically today and damage your domain's reputation.


In general, deliverability is a very important factor, because all the efforts of marketers, designers, and other members of your team can be in vain if your emails do not end up reaching the recipient.


In this article, let's figure out what problems with email deliverability can arise, how to find them, and how to fix them.


The main categories of deliverability problems are:

1. Email content.
2. IP reputation, domain, and email address.
3. Server configuration.
4. Bounces, complaints, spam traps.


The first thing to do is figure out what problem you have.

To do this, you need to study reports by email and analytics. You can do this with your mailbox provider. Almost all mailbox providers give you access to your email analytics.


We at Warmy have all the necessary tools to check your email and after connecting your email to our tool you can immediately see all the email deliverability errors that you have in your mailbox.



1. Email content


The content of your email has a huge impact on email deliverability, what you write about, what words you use, links, pictures, etc. Email content includes HTML code, text part, and subject line


Artificial intelligence is getting smarter from year to year, it analyzes not just individual words, but the entire text follows links, and draws a conclusion about the quality of your content.


Test your template in our free tool - template checker and you will immediately see what mistakes were made.

After that, the ideal option is to start A/B testing your message. Email is the perfect place to test. Start by changing the subject line of your email. Then content, links, pictures, CTAs, etc.


2. IP reputation, domain, and email address


If you start to notice that your mailings are getting into spam more and more often, then something is wrong with the reputation of your IP.


Spam filters have blacklists of email addresses that are marked as spammers. Before e-mail content is checked, the IP address is checked for whitelist or blacklist. If you are blacklisted, your emails will end up in the Spam folder.


There can be many reasons why IP is included in such blacklists, we will not dwell on them in detail now. The most common cause of your IP getting into spam is the actions of email recipients. If several recipients have marked letters received from your address as spam, the IP is sent to the "blacklist"


Use Warmy to check if your IP is blacklisted. You do not need to additionally check your IP in each blacklist, our tool automatically checks this for you. If your email is seen on one of the lists, Warmy will show it to you.



After that, you can take the necessary actions to ensure that your domain or IP is excluded from the blacklist.


How to remove an IP from the blacklist


If you see that domain reputation is the cause of email deliverability problems, you need to restore it. This is done by gradually warming up your email to show that your domain is trustworthy. Tools such as Warmy, using artificial intelligence, develop a separate strategy for each mailbox and automatically warm up the email, while increasing the reputation.


3. Server configuration


Perhaps the emails are not even sent from your server due to a configuration error.


Misconfiguration of the mail server, namely the absence of authentication records such as SPF and DKIM, can also cause email deliverability problems.


To check the configuration, you need to view the mailbox health report in Warmy.



If you have unconfigured or incorrectly configured SPF, DKIM, and DMARC records, you will immediately see this. After that, you need to fix all the necessary errors.


Why do you need to configure SPF, DKIM, and DMARC?


Our specialists will tell you how to fix all problems with the mailbox, help you set it up, and prepare it for proper warming up.


4. Bounces, complaints, spam traps


If your recipients mark your email as spam, it greatly affects your domain's reputation in the future. After several such complaints, your email may be blacklisted.


How to work with it:


1. Don't use a purchased subscriber base.
These databases often contain spam traps. A spam trap is an email address used by ISPs and anti-spam organizations to identify scammers and combat spam. If your newsletter falls into the spam trap, it will damage your reputation. The worst-case scenario for a sender is to fall into multiple spam traps at once.


2. Remove uninvolved users.

Those who do not respond to your letters, do not open them, but immediately delete them should be excluded from your mailing list. Practice shows that such subscribers will not benefit your business anyway, so feel free to delete such addresses.


3. Use double subscription confirmation.

What does double opt-in mean? A double opt-in occurs when a user signs up for an email marketing list, and then an email is sent out to the user which includes a link to click and confirm the subscription. Only after the confirmation click is completed will the user officially be added to the email marketing list.


4. Ask your loyal customers to mark your email as important if it ends up in Spam.


Start fixing email deliverability issues with Warmy - Auto all-in-one tool to make your email channel reliable | Product Hunt