Maybe you have a free trial version of Office 2007, and the trial period
has ended. Or maybe you have not activated your Office software.
What happens if you start Word 2007 and click on Office Button | Word
Options | Resources | Activate? If you are already activated, a dialog
box saying so will appear. If you are not activated, the Activation
Wizard will start. If you have an expired free trial version, a dialog
box will prompt you to enter a valid product key or convert (purchase a
key) online.