Use Exchange Rich-Text Format
If enabled, POP3 clients receive messages in Exchange Rich Text Format (RTF). Although all POP3 clients receive the information as an attachment, the attachment is opened and displayed as a normal message for POP3 clients that understand Exchange RTF. For POP3 clients that do not understand Exchange RTF, an attachment is displayed. By default, Exchange RTF is not used.
To use Exchange Rich Text Format:
Note If you want to use Exchange rich-text format, the only MIME option available is plain text.