RTF-formatted messages are not supported in Mail Express 3.1 and later. The procedures below describe how to change the message format, depending on your version of Outlook.
To change the message format for all messages
Click the File tab.
Click Options.
Click Mail.
Under Compose messages, in the Compose messages in this format list, click HTML or Plain Text.
To change the format of an individual message
With the message open, click Format Text.
On the Format tab, click the format you want to use (Plain Text or HTML).
To change the default message format for all messages
On the Tools menu, click Options, and then click the Mail Format tab.
In the Compose in this message format list, click HTML or Plain Text.
To change the format of an individual message
With the message open, click Options.
On the Format tab, click the format you want to use (Plain Text or HTML).