Office 2002 - Office 2007

To delete/reset the Product Key of Office 2007 or previous we have to go into the Registry. To open the registry, click Start, and then click Run. Type regedit in the open box and click Ok.

1. Browse to the following key of the Registry:
   • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\\Registration
2. It is a good practice to backup the Registry keys before modifying them so make a backup of that key; Right click on the key, choose Export… and save the file somewhere safe.
3. Expand the Registration key in the Registry and you’ll see one or more sub keys which contain a lot of characters between curly brackets: { and } Each sub key stands for an installed Office application. The proper name for this identifier string is called a “GUID”.
4. Click on the sub key to reveal its contents in the right pane. The SuitName key will reveal the name of the package that you have installed. If you have multiple GUID sub keys listed, you can use this key name to determine for which installation you’ll be changing the Product Key.
5. In the pane on the right, delete the following keys:
   • DigitalProductID
   • ProductID
6. Close the Registry and start Outlook (or any other Office application); you’ll now be prompted to fill in your Product Key and activate Office again.

Office 2010 and Office 2013

Changing the Product Key for Office 2010 or Office 2013 doesn’t require any changes to the Registry and can be done directly from the Control Panel. To change it, open the “Add/Remove Programs” applet or the “Uninstall a Program” applet (Windows Vista or later). Locate your Office 2010/2013 application and press Change. Setup will now start with the option “Enter a Product Key” which allows you to enter a different product key.