What does this error mean?
The domain has exceeded the maximum number of deferred emails and transmission failures per hour
Domain mydomain.com has exceeded the maximum number of times per hour (x / x (xx%)) allowed
If you receive an error similar to “Domain mydomain.com has exceeded the allowed per hours (x / x (xx%) allowed” in an email bounce, this means that outgoing e-mails from your domain have triggered a rule in the server that will prevent any other email from coming out of the server.
This occurs when a domain account sends e-mails that fail or are delayed. If the number of failures is greater than the server limit, no other mail will be allowed to exit for an hour.
How to identify the cause of the error;
This error comes from a time monitoring system, in which all blocked domains are allowed to send emails one hour after the first error.
For example, if the blocking occurs after 5 errors and the first error was notified at 13:12 but 4 others were done at 13:45, the blocking will start at 13:45 but will end at 14:12 (where the first error disappear due to the one hour wait)
The 4 other errors will still be active until 14:45 but without blocking unless a new error occurs (which would block until 14:45)
If you do not know exactly what is causing it, you can probably find out by using the Track Delivery icon in your cPanel.
When you click on the Track Delivery icon, a field appears where you can enter the recipient’s email address. Then click on the “Run Report” button to get information about the emails sent to this recipient.
If you do not enter anything for the recipient’s email address, you will be able to retrieve the data for all email traffic.
You will then see groups of returned messages that can help you determine which sender caused the problem and why.
What should you do to prevent/fix this?
There are two circumstances in which this will happen:
- You send a lot of emails and some in your mailing list are inactive
- Your account has been hacked and is used to send spam
If you send mass emails
If you send emails en masse and this happens, it probably means that some of your subscribers are no longer using the email addresses they subscribed to.
You will need to clean up your mailing list and stop sending emails to these inactive accounts.
The Track Delivery tool in your cPanel, which will help you identify inactive emails and clean up your mailing list.
If you do not send bulk emails
If you do not send mass emails but receive the “max defers and failures per hour” bounce message, it may mean that your account has been hacked.
Before you panic, follow the steps above to identify recently sent emails from your account.
If you do not recognize most of the email addresses in the Email Tracking report, you must update the email account password used to send these emails.
You will also need to put a captcha on the sending forms on your site.