How do I... Add my existing Gmail account to Windows Mail?
Source: Greg Shultz
Google has added IMAP capabilities to Gmail, thus making it possible for you to access your Gmail account in Windows Mail. With IMAP capabilities built into Gmail, you have the ability to use both Windows Mail and the Web-based interface at the same time. In this edition of the Windows Vista Report, Greg Shultz shows you how to configure Windows Mail to send and receive e-mail messages from Gmail's server.