0 votes 0 votes Some email systems support a Content Return: header field. It specifies whether the body of a message is to be returned in the event of nondelivery. Does this field belong to the envelope or to the header? Computer Networks computer-networks tanenbaum descriptive application-layer-protocols + – ajaysoni1924 asked Mar 19, 2019 ajaysoni1924 445 views answer comment Share Follow See all 0 reply Please log in or register to add a comment.