When Messaging Gateway (SMG) annotates messages, in some cases the final message contains the annotation text with the original message as an attachment rather than the annotation being merged with the original message text.
In some cases, the annotation cannot be seamlessly merged with the original email message's MIME structure. In this case, to preserve the original message, SMG creates a new message with the original as an attachment and the annotation as the message body. This is to ensure that merging the annotation with the original message does not cause a loss of information or otherwise render the original message unreadable.
This is an expected and correct behavior for email messages that cannot be successfully restructured to accommodate the HTML annotation and the message body.
This behavior can be observed when HTML text is used for the annotation. Please use plain text annotations instead, which have been observed to resolve the conflict and render the message and annotations within the message body.