Thammarat charoenchai. wrote:

I'm use Outlook 2007. Thanks.

In Ouitlook 2003, one would click ToolsOptionsMail FormatFonts to change
the Reading Pane fonts (the "When composing and reading plain text"
setting). Naturally, this will affect the Plain Text messages only. HTML
and Rich Text messages use the fonts the sender specified.
--
Brian Tillman