Trace back NDR (Non Delivery Reports)

Hi All,

I have one demand, that requires to trace back mail messages… for exemple:

I send a mail to a non existing address, i receive a mail from my router, saying that could not find the receipt (NDR mail)

But is generated another NOTE ID for this NDR mail.

The NDR save the original NOTE ID??? Where???

Othe question, in what situation destination servers can block to send NDR reports? is this possible?

Best regards, Abraços,

George Araujo