If you encounter a Windows Genuine Advantage (WGA) message that there is a problem with the product key or the volume license key for your installation of Microsoft Windows XP or Windows Vista, use one of the following methods to resolve the issue.
If you have the original media or the Certificate of Authenticity (COA) with a product key, visit the Compare Product Key Web site for resolution:
Contact the reseller from whom you purchased the software and request Genuine Windows software. Microsoft can provide a report to help explain the situation to the reseller. If you plan to use this option, visit the following Web site to try validation:
If validation is unsuccessful, select see all options, and then select Go back to your reseller. Next, follow the instructions for returning to your reseller to receive Genuine Windows XP software.
Purchase a full packaged product (FPP) version of Windows XP from a retailer.
Microsoft will send a complimentary copy of Windows XP to customers who have been sold a high-quality counterfeit version of Windows XP. You must submit proof of purchase, the counterfeit CD, and a counterfeit report that includes details about the purchase. To obtain more information about the Complimentary WGA Kit and to apply, visit the following Web site to try to validate the software, and then select See all options
After validation is unsuccessful, click Complimentary WGA Kit.
Purchase the Windows XP Home or Pro WGA Kit online at a reduced price (estimated at $99 for Windows XP Home, $149 for Windows XP Pro). With this option, a new product key will be e-mailed to you after payment is confirmed. You will also receive the Windows XP CD and media by mail within four to six weeks. The kit will include Windows XP Service Pack 2. When you use the kit, you may have to reinstall the operating system. To purchase the WGA legalization kit, visit the following Web site to validate your software, and then select Buy Now after validation is unsuccessful:
Click Select a product, and then select Windows Genuine Advantage.
First, verify that your software was installed by using the correct product key. If an incorrect product key may have been used, try to update the product key, and then try to validate again. To update the product key, try to validate the software by visiting the following Web site:
Obtain technical support. In rare cases, technical support may be needed to identify and resolve your validation issue. To determine the best technical support option for your issue, visit the following Microsoft Genuine Advantage Web site, and see the "Get Technical Support" section: