http://blogs.msdn.com/b/charles_sterling/archive/2006/11/07/visual-studio-2005-tools-for-the-2007-office-system-has-been-released-to-the-web.aspxIf you want to do Office 2007 development this is a must have! Brief Description Install VSTO 2005 SE to create new application-level add-ins for six applications in the 2007 Microsoft Office system and five in Microsoft Office 2003. Use manageden-USTelligent Evolution Platform Developer Build (Build: 5.6.50428.7875)