4.5.1 Email Bounce Error
Reason
Bad Messaging Command In Transmission: Delayed Message
The email message has not yet been delivered because the sender’s email provider used a messaging command that was unsupported.
How to fix?
Retry the email message see if it was a one-time problem or if the same error occurs. Otherwise, contact the support team as the sender’s mail system issued a command that is not supported by the recipient’s email provider. This typically requires help-desk support.
4.5.1- 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.5.1
A mail transaction protocol command was issued which was either out of sequence or unsupported. This is useful only as a permanent error.
5.5.1 Email Bounce Error
Reason
Bad Messaging Command In Transmission: Message Not Delivered
The message could not be delivered because the sender’s email provider used a messaging command that was unsupported.
How to fix?
Retry the email message see if it was a one-time problem or if the same error occurs. Otherwise, contact the support team as the sender’s mail system issued a command that is not supported by the recipient’s email provider. This typically requires help-desk support.
5.5.1- 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.5.1
A mail transaction protocol command was issued which was either out of sequence or unsupported. This is useful only as a permanent error.