How to change the product key for Office XP, for Office 2003, and for 2007 Office programs and suites
SYMPTOMS
You cannot change the product key for Microsoft Office XP, for Microsoft Office 2003, or for the 2007 Microsoft Office programs and suites without first removing and then reinstalling Microsoft Office.
RESOLUTION
To resolve this issue, follow the steps in this section.
Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.Note If you try to open any Office programs after you complete the steps, you receive a message that prompts you for a valid product key. Have a valid product key on hand before you start the steps.1. Close all Office programs.
2. Click Start, click Run, type regedit, and then click OK.
3. Locate and then click the following subkey:
For 2007 Office programs and suites:
HKEY_LOCAL_MACHINE \Software\Microsoft\Office\12.0\Registration
For Office 2003:
HKEY_LOCAL_MACHINE \Software\Microsoft\Office\11.0\Registration
For Office XP:
HKEY_LOCAL_MACHINE \Software\Microsoft\Office\10.0\Registration
4. Export the Registration subkey.
You can make a backup of the values under the Registration subkey if the new product key does not work. To do this, follow these steps: a. Right-click the Registration subkey, and then click Export.
b. In the Save in list, select a location to save the registration entries.
c. In the File name box, type a name for the .reg file that you want to export, and then click Save.
Note In steps 4a through 4c, you created a backup of the Registration subkey. You can restore the Registry settings of the Registration subkey by double-clicking the .reg file that you saved in step 4c. The contents of the .reg file are automatically exported to the Registry.
5. Under the Registration subkey, there may be several Globally Unique Identifiers (GUID) that contain a combination of alphanumeric characters. Each GUID is specific to a program that is installed on your computer.
Click a GUID. Then, view the version of Office that is listed in the right pane for the Productname registry entry. After you find the GUID that contains the version of your Office program, follow these steps: a. Right-click the DigitalProductID registry entry, click Delete, and then click Yes.
b. Right-click the ProductID registry entry, click Delete, and then click Yes.
For more information about how to identify the correct GUID for the version of the Office suite or program that you have installed on your computer, click the following article numbers to view the articles in the Microsoft Knowledge Base:
928516 Description of the numbering scheme for product code GUIDs in 2007 Office suites and programs
832672 Description of numbering scheme for product code GUIDs in Office 2003
302663 Description of the numbering scheme for product code GUIDs for Office XP programs
6. Close Registry Editor.
7. Open an Office program, such as Microsoft Word. When you receive a message that prompts you for the product key, type the correct product key, and then click OK.