Use the AlternateView class to specify copies of an e-mail message in different formats. For example, if you send a message in HTML, you might also want provide a plain text version in case some of the recipients use e-mail readers that cannot display HTML content.
Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.