Microsoft has said it will be a challenge to convince some consumers to buy its new version of Office.
Office, the world's most popular productivity suite, includes Word, Excel, Outlook and other tools.
"One of the biggest challenges... is to fight that perception that old versions of software are good enough," said Microsoft's Chris Capossela.
Office 2007 goes on sale to business on 30 November, the same date new operating system Vista is launched.
"Our business model of course allows you to keep using Office 2003 - the software doesn't really expire, " said Mr Capossela, corporate vice president of the Microsoft Business Division.