This blog post provides an overview of the different response codes that can be generated by an SMTP (Simple Mail Transfer Protocol) server when sending an email. SMTP response codes are three-digit codes that indicate the outcome of an email delivery attempt. The post explains the most common SMTP response codes, including “200 OK,” “450 Requested action not taken: mailbox unavailable,” “550 Requested action not taken: mailbox unavailable,” and “554 Transaction failed.” The blog also covers the meaning and implications of these response codes for email senders and provides tips for resolving common issues related to SMTP response codes. The key takeaway from the post is that SMTP response codes are an important aspect of email delivery, and understanding them is crucial for improving email deliverability and ensuring that emails are being sent and received successfully.
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Not sure what an SMTP error code means? You’re not alone. It can be shocking and confusing to see SMTP errors sometimes, and we want to eliminate the confusion with a quick-and-easy explanation. Below, we’ll explain everything you need to know about SMTP error codes, including short explanations of common ones you’ve likely seen before. What is an SMTP error code? Within the SMTP process, messages are relayed from one computer to another via SMTP servers. SMTP servers send response codes that indicate what has happened to messages. While messages are usually sent without issue, different server response codes can
SMTP Error Codes: What Do These Server Responses Mean? | SendGrid was originally published on SendGrid Email Deliverability Blog | SendGrid