In Exchange, incoming SMTP messages are missing information in the To field, the From field, or the Subject field

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This behavior is possible if the sending mail product does not provide this information in the P2 (Body) of the message. This behavior can be reproduced in the following manner.

Note <CRLF> represents carriage-return/line-feed or the use of the ENTER key. For the To, From, and Subject fields to be populated, the sending mailer must populate that information in the data section. The behavior described in the "Symptoms" section does not break any RFC; however, it is not a recommended, preferred, nor appreciated behavior for a mail system to engage in.