If you are receiving an error similar to “Domain has exceeded the max defers and failures per hour (5/5 (100%)) allowed“ in an email bounceback, it means that outgoing email from your domain has triggered a rule on the server that will stop any further email from going out of the server.
- This happens when an account sends out emails that either fail or get deferred.
- This block is temporary and typically clears automatically at the top of the hour
- This error occurs to protect your account from being listed as a spam email.
- If you don't recognise the failed emails, your account may be compromised. Immediately change your email password.
- Check web forms: Ensure any contact forms on your website are properly secured with CAPTCHA and are not being exploited by bots.
- Check the cause: Log into your cPanel and use the Track Delivery tool. Review the preceding failed emails and confirm whether you are sending to mistyped addresses or whether your account has been compromised to send spam.
