Howto: Change Product Key without a Reinstall for WGA
Contributed by MickeyMouse 
Tagged: Windows installation Windows Genuine Advantage is now a required install. If you need to change your product key without an installation to make WGA happy, these steps will walk you through it. This uses Microsoft-supported software. This is how I explore “You May Be a Victim of Software Counterfeiting” errors.
Many of our users at work have been receiving the You May Be a Victim of Software Counterfeiting error. Basically what happened was that the notebooks were mailed with invalid product keys.
Surprisingly for many people, the Certificate of Authenticity (COA) or supplied valid product key may not be the actual one in use on their desktop computer or laptop. These numbers can be found on your XP software box or on a COA sticker on your system.
First, compare the product key on your XP installation to your valid xp product key or COA number using WGA Diagnostic Tool.
If the numbers are different, you can usually change your number to a valid one by using Microsoft’s Key Update Tool.
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deyamag said on February 3, 2009
If more explnation.
thanks anyway.
Anonymous said on August 24, 2009
Using Ghost we cloned one computer onto another, faster etc. Using the diag tool the key is showing ok even though the product label on the computer does not agree. Should I change it to match the computer or leave it alone? The old computer will probably be recycled.
Anonymous said on March 4, 2010
Hi. I’ve tried everything you have suggested to ensure my software is genuine but to no avail. I’ve located the original product key, but when I use the “tool”, it says that these numbers match the product key given and therefore it won’t update my system. I have to tell you that I downloaded the “trial” version of Microsoft 2007 and uninstalled it after the trial was over. I have ALL the product keys (XP and 2007 and 2002 Publisher), but I still receive messages that my product may not be genuine. Do I have to purchase the genunie advantage? Thanks for your help!
MzBlondage said on July 2, 2010
that works with XP so how do i get past WGA on 7 or vista?