If you are preparing to reinstall Windows XP, you will need to find a copy of your Windows XP product key - also known as a CD key. Typically, this product key is on a sticker on your computer or placed with the instructions that came with Windows XP.
If you lost a copy of the product key, do not worry. While it is in the registry, it is encrypted and unreadable, making it difficult to find it.
Follow the steps below to locate your Windows XP product key:
Manually locating the Windows XP product key from the registry is almost impossible due to the fact that it is encrypted.
Note: The manual techniques used to locate the product key for operating systems such as Windows 95 and Windows 98 will not work in Windows XP. These manual procedures will only find the product ID number, not the actual product key used for installation. Fortunately for us, some free programs exist to help find the product key.
2 Choose the free product key search program that supports Windows XP.
Note: Any product key finder that locates the Windows XP product key locates the Windows XP Professional product key as well as the Windows XP Home product key.
Tip: I used Belarc Advisor in the screenshot above. Most of the product key search engines in the above link will work fine with Windows XP, like Magical Jelly Bean Keyfinder, Winkeyfinder, LicenseCrawler and ProduKey.
Download and run the key finder. Follow any instructions provided by the software.
Most product key finders are really easy to use. With Belarc Advisor, finding a CD key is as easy as installing and running the program. The result will open in your default web browser and the product key is found in the Software license section.
4 Numbers and letters are displayed by the key finder that represents the Windows XP product key.
Product key must be formatted like xxxxx-xxxxx-xxxxx-xxxxx-xxxxx - five sets of five letters and numbers.
5 Write down the product key exactly when the program displays that code for you to use when reinstalling Windows XP.
Important: If even one character is written incorrectly, the installation of Windows XP that you tried with this product key will fail. Ensure accurate transliteration.
Most programs that offer you product keys will allow you to export the list of keys, including the Windows XP key, into the text file. Others allow you to copy text directly out of the program, which is true with Belarc Advisor.
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