Microsoft Office – You have not entered a valid product key
The following resolutions apply to the Microsoft Office 2007 and the Microsoft Office 2003 suite.
Method 1
If you installed a Microsoft Office 2007 suite from a retail box that you purchased from a retail store, then open Control Panel. Then, open Add or Remove Programs or Programs and Features and verify if there is another copy of an Office 2007 suite installed in addition to the suite you have already installed.
Preinstalled Office 2007 trial suites frequently conflict with the product key validation process. If you see a copy of Office 2007 suite installed, such as a trial version or a version labeled “2007 Microsoft Office system”, then uninstall that suite and the Office Activation Assistant. Then, enter the product key again when you are prompted.
NoteYou do not need to uninstall Office Activation Assistant if this item is not displayed in Add or Remove Programs or Programs and Features.
Method 2
The 25-digit product key that you found on a sticker on the bottom of your laptop or on your desktop case is not the correct key. This key is the product key for Windows and not for the Office 2007 suite. The correct product key for the Office 2007 suite will be in one of the following locations:
Inside the retail Office 2007 box if you purchased your product from a retail store.
In an e-mail message from the online Web site where you purchased the Office 2007 suite.
On a sticker located on the outside of the CD case.