4.7.5 Email Bounce Error
Reason
Message Authentication Issues: Delayed Message
The email message has not yet been delivered because your email sending system uses DKIM, an authentication mechanism. Either the sending or receiving email system had some problem with the sending system’s DKIM.
How to fix?
Check if it is one time issues – retry sending message again after few hours. If problem persists you may need to dig out further to make sure it doesn’t have DKIM issues. If the problem continues, contact the sender’s email support team to help identify any misconfiguration with the sender’s account or with the email system.
4.7.5- Official definition from ITEF
For the code that starts from 4.X.X
A persistent transient failure is one in which the message as sent is valid, but persistence of some temporary condition has caused abandonment or delay of attempts to send the message. If this code accompanies a delivery failure report, sending in the future may be successful.
For the code that starts from X.7.5
A transport system otherwise authorized to validate or decrypt a message in transport was unable to do so because necessary information such as key was not available or such information was invalid.
5.7.5 Email Bounce Error
Reason
Message Authentication Issues: Message Not Delivered
The message could not be delivered because the email sending system uses DKIM, an authentication mechanism. Either the sending or receiving email system had some problem with the sending system’s DKIM.
How to fix?
Check if it is one time issues – retry sending message again after few hours. If problem persists you may need to dig out further to make sure it doesn’t have DKIM issues. If the problem continues, contact the sender’s email support team to help identify any misconfiguration with the sender’s account or with the email system.
5.7.5- Official definition from ITEF
For the code that starts from 5.X.X
A permanent failure is one which is not likely to be resolved by resending the message in the current form. Some change to the message or the destination must be made for successful delivery.
For the code that starts from X.7.5
A transport system otherwise authorized to validate or decrypt a message in transport was unable to do so because necessary information such as key was not available or such information was invalid.