http://developers.de/blogs/nadine_storandt/archive/2007/02/05/Compatibility-Pack-for-Office-2007-Files.aspxIf you receive Office 2007 Files and you don't have yet Office 2007 installed you can install the following pack and you will be able to open these files and save them. http://www.microsoft.com/downloads/details.aspx?familyid=941b3470-3ae9-4aee-8f43enCommunityServer 2008 SP1 (Build: 30619.63)