Stuck with Amazon SES SMTP Connection refused (111) error? We can fix it for you.

Quite often, when connecting apps to Amazon SES Mail service, users get errors. This happens mainly due to incorrect port settings, invalid logins, etc.

At Bobcares, we frequently deal with AWS errors as part of our AWS Support Services.

Today, we’ll see how our Expert Engineers fixed the SMTP error and made the emails work.

More about Amazon SES SMTP connection

In simple words, Amazon Simple Email Service aka Amazon SES allows users to send emails from their own domain names. Here, users do not have to invest time and resources to manage their own mail servers.

Moreover, Amazon SES integrates well with popular applications like WordPress and other AWS products too. That is why many app owners route their emails to Amazon SES Mail service.

Amazon SES SMTP connection allows sending emails using an SMTP username and password. This information lies at the AWS Management Console >> SES tab, under SMTP Settings.

What causes Amazon SES SMTP Connection refused (111) error?

Now that we have a basic idea of the Amazon SES, let’s get into the details of the error.

The customer was already having a WordPress website. It had a form that sends mails to the users.

To improve the email deliverability, he added a WP SMTP plugin, so that they can route mail via Amazon SES service. However, it reported

SMTP ERROR: Failed to connect to server: Connection refused (111) SMTP connect() failed.

Then the test email function interface showed up as:

Such connection refused errors can occur due to many reasons including:

Wrong SMTP login details

Many times, users add wrong SMTP login details. The Amazon SES SMTP login details are different from the normal AWS logins. Thus, the mail application will refuse to connect to the Amazon SES.

Port restrictions

Similarly, yet another common reason for connection refusal can be port restrictions. For the emails to work, the port sending emails should not be blocked on the server.

How we fixed Amazon SES SMTP Connection refused (111) error

We’ll now check how our Support Engineers fixed the Amazon SES SMTP Connection refused (111) error for the customer.

As the first step, we verified the SMTP login details from the AWS SES interface. Then we confirmed that the customer was using the correct configuration in the WordPress mail settings. This included the SMTP host, port, encryption settings, etc.

Next, we checked whether the connection to the mail server was working correctly from the WordPress server. However, the connection on port 465 was failing.

$ telnet email-smtp.xxx-2.amazonaws.com 465
Trying 35.xx.yy.92...
telnet: Unable to connect to remote host: Connection refused

And that resulted in the connection refused error.

It was not allowing connection out from our server due to a port/firewall problem. Therefore, we opened the outbound 465 connection on the server firewall. Thus, the port 465 connection started establishing successfully. Finally, mail started working fine too.

[Need help in debugging Amazon SES errors? We are available 24×7.]

Conclusion

To sum up, Amazon SES SMTP Connection refused (111) error happens due to email port restrictions, wrong login credentials, etc. Today, we saw how our Support Engineers resolved the error and made emails working on a WordPress website.