Are you getting SMTP error 452 when sending mails?

The 452 too many recipients error mainly happens due to message overload. When we try to send too many emails at once, the server storage limit exceeds and results in this error.

At Bobcares, we often receive requests to fix the SMTP error 452 as part of our Server Management Services.

Today, let’s discuss this error in detail and see how our Support Engineers fix it for our customers.

What causes SMTP error 452?

Usually, the SMTP server reply to every client request with a return code. And, this code contains three numbers.

The first number indicates the server acceptance of the command. The second and third gives a clear description of the error.

Recently, one of our customers approached us with an SMTP error. When he tried to send more than 1000 emails, he got the following error.

SMTP error (452): Failed to add recipient
(4.5.3 Error: too many recipients)

Our Support Engineers checked and found the error with the overloaded mail server. In an attempt to send too many emails at once, the server went out of storage space.

Here, the number 4 indicates the temporary failure of the server. Now, let’s discuss some top fixes for the error 452.

Fixing the error 452

For security reasons, every server allots certain email limits for each domain. So, If the number of emails sent exceeds the limit, then it returns the error 452. This is a desired feature to avoid bulk mailing from the server. This comes handy when spammers use any compromised email account.

Unfortunately, this creates a problem when a customer wants to send too many emails at once.

Let’s now check how our Support Engineers use different ways to fix this error effectively.

1. Mailing lists

One of the best methods for bulk mailing is Mailing lists.

The Mailing list feature in cPanel enables us to send emails to many recipients at the same time. cPanel uses the Mailman list manager to provide this functionality.

To create a mailing list, we follow the below steps,

1. Firstly, log in to the cPanel.
2. Then, navigate to Email>>Mailing Lists.
3. After that, we give the mailing list name in the List Name text box.
4. We will add the mailing list password in the Password text box.
5. Next, under the Access type, we choose Private or Public.
6. Finally, we click on Add.

2. Increasing the limit

We have another option to set email limits for particular cPanel accounts. For that, we log in to the cPanel>>Tweak Settings.

There is an option to set maximum hourly emails per domain. For domains that need to send too many emails, we set the limit to a higher value.

3. Using third-party email services

Some customers need to send marketing emails frequently to their users. When they try to send too many emails, the server may block the emails.

Therefore, to send emails regularly to more participants, we recommend customers to use third-party email services like MailChimp, Sendgrid, etc.

4. Splitting the recipient list

At times, these third party mailing services may not be affordable to certain users. In such cases, customers may need a cost-effective method to send more emails at once.

Therefore, we suggest customers break the recipient list into chunks having fewer email addresses. And send one of the chunks each hour.

This method resolves the error of sending too many emails at once.

[Need more help to fix SMTP error 452?- We’ll help you.]

Conclusion

In short, the SMTP error 452 too many recipients occurs when the server has insufficient space and gets overloaded. In today’s article, we discussed the main causes of error 452 and saw how our Support Engineers fix it for our customers.