Exchange can send messages in HTML, rich text, or plain text formats. Although not all clients display HTML or rich text properly, there are situations where the HTML format is needed.
We've explained how to send HTML-formatted messages to specific domains in Exchange 5.5 ("Send HTML messages to specified domains," March 10, 2003). Here's how to do the same in Exchange 2000:
Exchange will now use the HTML format when sending mail to the selected domain. You can create as many of these custom formatting policies as your organization needs.