4.6.5 Email Bounce Error
Reason
Message Content Not Accessible To Recipient Server: Delayed Message
The email message has not yet been delivered because it included content or attachments that needed to be converted but that was not completed.
How to fix?
If the message had attachments, try sending it again without them and then try sending each attachment in a separate email. If this error occurs when there are no attachments, check the text of the message for unusual content or characters
4.6.5- 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.6.5
A conversion was required but was unsuccessful. This may be useful as a permanent or persistent temporary notification.
5.6.5 Email Bounce Error
Reason
Message Content Not Accessible To Recipient Server: Message Not Delivered
The message could not be delivered because it included content or attachments that needed to be converted but that was not completed.
How to fix?
If the message had attachments, try sending it again without them and then try sending each attachment in a separate email. If this error occurs when there are no attachments, check the text of the message for unusual content or characters
5.6.5- 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.6.5
A conversion was required but was unsuccessful. This may be useful as a permanent or persistent temporary notification.
