4.1.9 Email Bounce Error
Reason
Message Routed To Non-Email System: Delayed Message
The email message has not yet been delivered because recipient’s domain is not set up to handle email.
How to fix?
Check your recipient’s domain in the recipient’s email address for misspellings or missing letters. If an error is found, correct it in contacts list or address book for next time.
4.1.9 – 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.1.9
The mailbox address specified was valid, but the message has been relayed to a system that does not speak this protocol; no further information can be provided.
5.1.9 Email Bounce Error
Reason
Message Routed To Non-Email System: Message Not Delivered
The message could not be delivered because the recipient’s domain is not set up to handle email.
How to fix?
Check your recipient’s domain in the recipient’s email address for misspellings or missing letters. If an error is found, correct it in contacts list or address book for next time
5.1.9 – 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.1.9
The mailbox address specified was valid, but the message has been relayed to a system that does not speak this protocol; no further information can be provided.