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In Word 2007, click the Office icon, then Options > Advanced > General > Web Options button > Fonts. In Word 2010 and newer, go to File > Options > Advanced > General > Web Options button > Fonts and select a different font. When a default font is not included in an HTML message, Outlook uses the default web font. To set the default HTML font in Outlook 2007 and newer: Messages that don't have a default font set use the default Web Font set in Microsoft Word Options. You cannot easily control the font used to read HTML messages, since most people who send HTML mail specify the font they want their messages to appear in.
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The middle two options, for New mail messages and Replies and Forwards, controls the default fonts used for HTML and RTF messages and apply only to messages you send.
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In Outlook 2007 and newer, you can change the fonts used for reading plain text messages from the Stationery and Fonts dialog in Options. Plain Text | HTML | Rich Text | WordMail | More Information Outlook 2010 and newer See Adjusting Outlook's Zoom setting for more information. Instead of changing the font in messages, you can adjust the Zoom.
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