[frik]

Outlook 97-2013 use Word for the compose window. It's not an option, it's how it works behind the scene (Win32 COM components).

e.g. an known Outlook 2010 bug (with Exchange 2013) crash the Outlook client on startup. But you can still open *.msg files, it opens the mail in a window and one can edit the mail.

It's all about Bill Gates vision "information at your fingertips" from the early nineties and the Cairo operating system.

Watch this video from Bill Gates Comdex '90: http://youtu.be/kL8zoQVJaD8?t=19m26s

Cairo '91-'96: https://en.wikipedia.org/wiki/Cairo_operating_system

[yuhong]

Outlook 97-2003 has it as an option, 2007+ don't. And BTW the Outlook 97-2003 and 2007+ implementations of this feature are different too (MS split most of Word into wwlib.dll in Word 2007).