SMTP Errors

Errors, their explanation and solutions

  • Invalid email address error codes

    Last Updated: 03.01.2024

    If you send bulk emails, you may face the problem of delivery errors. Knowing the reasons will help you cope with it and increase conversions. After registering with SendPulse, you're welcome to monitor your campaign statistics, including the errors. Keep on reading this article to discover the causes and ways to avoid errors.

  • The 550 5.1.1 error

    Last Updated: 03.01.2024

    There are several possible reasons that you received this error. In this guide, we'll talk about the reasons and help you resolve this nasty error.

  • Spam related delivery errors

    Last Updated: 03.01.2024

    You may receive the following errors: SMTP Error 450 4.7.1

  • Error 503

    Last Updated: 26.09.2024

    Have you ever faced Error 503 – Valid RCPT command must precede DATA while sending emails?

  • How to fix SMTP sending errors

    Last Updated: 28.12.2023

    Sending messages via an SMTP server may be accompanied by errors. These errors may occur due to mail server inaccessibility, sender authentication issues, exceeded limits, mistyped email addresses, and so on.

  • The 554 5.7.1 SMTP error

    Last Updated: 26.09.2024

    When sending an email, you should take into account two mailing servers: yours and the recipients.

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