SMTP Error 450:

What does it mean? And How to resolve this error.

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Error Description

SMTP error 450 is a transient or "4xx" error code returned by a mail server to indicate a temporary issue with the recipient's server that prevented the delivery of an email message. This error suggests that the recipient's server encountered a problem or was temporarily unavailable, causing a delay in email delivery.

What's Causing This Error?

SMTP error 450 is typically caused by temporary issues on the recipient's side, including:

Server overload: The recipient's mail server may be experiencing high traffic or resource limitations, resulting in a temporary inability to process incoming messages.
Connection issues: Problems with the network or server infrastructure can lead to temporary delivery failures.
Message size or content issues: The recipient's server might have restrictions on email size or content, causing email delivery delays.
Greylisting: Some servers use greylisting as an anti-spam measure, which can delay the delivery of emails from unknown senders until the message is reattempted.

How to fix SMTP Error 450?

Wait and retry: In most cases, SMTP error 450 is temporary, and the best approach is to wait and resend the email message later.
‍Check recipient's server status: You can check if the recipient's server is experiencing issues or downtime by contacting their email administrator or checking their status page if available.
‍Review email size and content: If the email message is very large or contains unusual content, consider optimizing it to meet the recipient's server requirements.
‍Contact the recipient: If the issue persists or is a recurring problem, you may contact the recipient to inquire about the status of their email server.