Outlook gives you three message format choices. If the recipient's email program is set to convert messages, for example, then a message you send formatted as HTML could be converted to plain text. How the message appears to the person receiving it depends on their email program.
If someone sends you a plain text message, for example, you can reply to that message or forward it by using HTML or Rich Text Format. You can change the format of a message when you reply to it or forward it.
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