To help stop spam, we have started monitoring the number of emails that each account sends out which result in bounce backs. If our system detects that 10% or more of the emails being sent out from an account are resulting in defers or failures (bounce backs), the system will prevent the account from sending out any further emails for up to one calendar hour.
In other words, if 10% or more of the emails sent from your account within a one hour period bounce back, the system will prevent you from sending out any further emails for up to one hour. You will know this has occurred when you get an immediate bounce back that says:
This message was created automatically by mail delivery software. A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: [email protected] Domain your-domain.com has exceeded the max defers and failures per hour (5/5 (50%)) allowed. Message discarded.
There are generally two circumstances under which this will occur:
- You are sending out mass emails and some of the addresses in your mailing list are inactive
- Your account has been hacked and is being used to send out spam by a malicious user
What should you do to prevent/fix this?
If you are sending out mass emails
If you are sending out mass emails and this has occurred, it most likely means that many of your subscribers are no longer using the email addresses that they subscribed with. You will need to clean up your mailing list and stop sending these inactive accounts your emails. Within cPanel there is a tool called "Track Delivery" which can assist you in cleaning up your mailing list.
- Log into cPanel
- Click on the Track Delivery icon
- Leave the Recipient Mail field blank and Click [Run Report]
- Information about all the emails sent out from your account will be displayed. Use the information provided to determine which email addresses you should stop sending emails out to and remove them from your mailing lists
If you are not sending out mass emails
If you are not sending out mass emails but are getting the "max defers and failures per hour" bounce back message, it might mean that your account has been hacked. Before you panic, follow the above steps to see what emails have been sent out from your account recently. If you do not recognize many of the email addresses in the Email Trace report you should update the password for the email account that is being used to send out these emails.
Check autoresponders and spam filters. This block can sometimes be triggered when you have an autoresponder setup to send an out-of-office reply to all emails you receive. This is because the autoresponder will reply to all emails including spam email addresses which do not exist. In these cases the reply will fail which counts towards the delivery failure count per hour on your domain. To resolve this ensure your Spam Filters are enabled on your Indichosts hosting account. This will ensure emails we flag as spam are not sent an autoresponse.
How can I fix this?
This error is derived from an hourly monitoring system, where any blocked domains are allowed to send email again at the top of every hour. For example, if you received this error at 2:45pm, the block will release at 3:00pm and the domain will be able to send emails out once more.
If the problem continues, then contact us if you require further assistance.