PC is broken, how to tell if XP key is genuine?

[Petef56]

I have a broken PC here and need to reinstall Windows XP Pro to fix it.
I have a WinXP Pro CD and the PC owner gave me his Win XP Pro
in handwritten form. Before I begin, I'd like to find out if this key is
valid/genuine. If I find out the key is not genuine, I will not
repair this PC.

I am aware of www.microsoft.com/genuine for valuidation testing,
but that requires the PC to be tested to be working.

Is there any other way to check if a key is valid by just providing
the key? Any phone number to call at MS where I could have this
checked?

---pete---

[shadowpr]

You could just ask him for his sticker.

[EzyStvy]

You can try the following if you want to go to the trouble.

The Magical Jelly Bean Keyfinder is a freeware open source utility that retrieves your Product Key (cd key) used to install Windows from your registry. It allows you to print or save your keys for safekeeping. It works on Windows 95, 98, ME, 2000, XP, Vista, Server 2003, Server 2008, Office XP, Office 2003, and Office 2007 family of products. It also has a community-updated configuration file that retrieves product keys for many other applications. Another feature is the ability to retrieve product keys from unbootable Windows installations. http://www.magicaljellybean.com/keyfinder/

[glc]

Q: Can I retrieve the product key from a non-booting Windows installation?
As long as both Windows versions are 2000, XP, 2003, or Vista, you can use the Load Hive function. You will have to slave the drive and point the Keyfinder to the non-booting Windows directory.

[Petef56]

Update:
Thanks all for your suggestions, but none would solve my problem
because the HD had failed and I simply needed to reinstall Windows
to a new HD. I just needed to know if the CD key the guy gave
me was genuine.

What I woud up doing was to call the Windows automated
activation number at.. 1-888-571-2048

I ignored the automated voice instructions and just said "AGENT"
several times and it switched me to a live person to speak to.
I explained my situation and she switched me to customer
support who simply asked what the CD Key code was and
a minute later she told me that it was a genuine number.

Problem solved

---pete---