How do I find my authentication code for windows 7

[Guest]

Hello, I have a genuine upgrade from Vista to Windows 7 professional. Last week it suddenly came up with non genuine copy of windows 7. Microsoft help won't help me without the authentication key (and I have lost the email and can't remember who I bought the copy from as it was online over a year ago.
Is there somewhere on my machine that tells me the code? cheers

 

[Shadow703793]

Is the OS installed? If it is installed, you can use this: http://www.magicaljellybean.com/keyfinder/
Use Magical Jelly Bean Keyfinder (free).