‘SMTP Error 453’ occurs due to temporary issues with the mail server while processing an email. This can happen if the receiving server is overwhelmed with traffic and unable to handle more emails at the moment. It may also be caused by resource limitations like insufficient storage or processing power on the server.
Another possible reason is incorrect SMTP settings, including wrong ports or authentication details. Additionally, if the email is flagged as spam or the sender’s IP is blacklisted, the server might respond with this error.
Resolving the Error – Solution
To resolve this error, initially, it’s often effective to simply wait a bit and then try resending the email, as the server issue may be temporary. It’s also important to check the SMTP settings in your email client, ensuring that ports, authentication details, and MX records are correctly configured.
If the issue remains unresolved, reaching out to the support team of the email service provider handling the receiving server can provide further assistance. They can investigate the issue in more depth and help in finding a solution.