Possible Duplicate:
How can I reinstall Windows 7 if I lost my installation DVD?
Edit: The answer was to find the Serial number first using a serial number finder utility. The possible duplicate was missing the additional condition that the serial number was missing.
I have Activated Windows 7 on my PC, But lost the CD and Serial number. I need to reinstall Windows 7, I (hope) can borrow a Windows 7 DVD somehow, but how do I get my original serial number, I have the product key as shown in System Properties.
Thanks for any ideas