Microsoft has released an update to Microsoft Office Word 2007. This update also contains stability and performance improvements to Word 2007. Generally, customers who purchase or license Word 2007 from Microsoft after January 10, 2010 for use in the United States and its territories must use updated software that doesn’t include a particular custom XML tagging implementation. You must install this update if you’re instructed by Microsoft in a separate communication. For technical details on the affected custom XML tagging functionality, please see KB978951.