How to Change Microsoft Windows and Office Product Keys

Sometimes a Microsoft product key shown in Belarc software doesn't match the key on the Microsoft sticker, or only shows a few characters of the key.  One common cause of this is that the software was pre-installed by the computer manufacturer and your personal product key was sent on a separate card or sticker.  Computer manufacturers often use their product key, instead of yours, when pre-installing software at the factory so that's the key you're seeing. 

Another common cause is that recent Office installers remove all but the last five characters of the install product key once the installation completes.

To change the product key currently on your computer (and reported by Belarc) to your full personal key, you can follow the steps outlined below.

Windows product keys

You can change your Windows product key by following the instructions at this Change Product Key Microsoft web page.  Those instructions work on many versions of Windows.

Finding your Office 2013 and later product key

Purchasers of Office 2013 and later usually receive only a Product Key Card and instructions to download office from the office.com web site.  The 25 character key on that Product Key Card is not your office install key, but instead an entitlement key allowing you to install office from that web site.

You can see the product key that is used to install office by signing into your office.com account here.  Once signed in, choose Install from a disc under Account Options.  You'll see your office installation product key to the right of your options.

Changing your Office 2010 and later product keys

You can change your Office 2010 and 2013 Professional Plus or later product key like this

  1. Open the Windows Control Panel and run "Uninstall a program" in the Programs group. (On Windows XP, just run the Add or Remove Programs control panel.)  You'll find the Control Panel on the Start menu or on Windows 8 by searching for it with the Search charm.
  2. Find and select the Office product you'd like to change the product key for in the list of programs.  Then click Change.
  3. In the resulting dialog box select the "Enter a Product Key" option and click Continue.
  4. Type your product key and select the option "Attempt to automatically activate my product online".  Then click Continue and on the next screen click Install Now.

Note: You must have an internet connection to reactivate Office online. However, you can also activate Office at a later time by opening any Office app, clicking on the File tab, and selecting Help.

Changing your Office 2007 and earlier product keys

You can change your Office 2007 (or older version) product key by following the instructions at the How to change the product key for Office XP, for Office 2003, and for the 2007 Office system Microsoft web page.