Reinstalled Windows 7 on Thinkpad Edge, activation key won't work

Hello, I am having trouble activating Windows on my laptop after a fresh OS reinstall and would appreciate any help you can give.

Specs:
Lenovo Thinkpad Edge 13
Processor: Intel U7300 1.3GHz
System: Windows 7 Professional 64-bit
RAM: 3 GB
Memory: 138 GB

Backstory:
I bought this laptop from a programmer friend in 2010. He had installed an OEM copy of Windows 7 pro (and there is nothing on the bottom listing the Windows product key). Recently I decided to install a fresh copy of Windows because it was slow and had too much crap on it. I ran Belarc Advisor to obtain the 25-digit Windows product key and other application product keys. I put a Windows install disk on a flash drive and reinstalled Windows 7 Professional 64-bit.

Problem:
However, when I try to activate Windows using the key that was registered to the device for the last 3 years, it says "The product key you have entered does not appear to be a valid Windows 7 key." I found a live support site for Microsoft problems, but after I explained the issue they tried to sell me another copy of Windows for $399.99 (WTF!). I tried Lenovo's online live support and they said to talk to Microsoft, not them.

Can anyone tell me if there is a way to activate Windows using the key I have, or do I have to obtain a new key? If I have to obtain a new key, do I have to reinstall Windows? With an OEM disk? Would I need to buy a Thinkpad OEM disk? What is the cheapest way to resolve this?

Follow up question: I'd like to sell this computer and buy something else. What do you think it's worth, assuming good/excellent condition?I believe at the time that I bought it in late 2010 it was worth around $800-900, and he sold it to me for $450.

Welcome to the Seven Forums

I bought this laptop from a programmer friend in 2010. He had installed an OEM copy of Windows 7 pro

Can you contact your friend and get the COA with the key on it?

However, when I try to activate Windows using the key that was registered to the device for the last 3 years, it says "The product key you have entered does not appear to be a valid Windows 7 key." I found a live support site for Microsoft problems, but after I explained the issue they tried to sell me another copy of Windows for $399.99 (WTF!). I tried Lenovo's online live support and they said to talk to Microsoft, not them.

Can anyone tell me if there is a way to activate Windows using the key I have, or do I have to obtain a new key? If I have to obtain a new key, do I have to reinstall Windows? With an OEM disk? Would I need to buy a Thinkpad OEM disk? What is the cheapest way to resolve this?

If you cannot get the COA key from your friend then the cheapest way and not have to reinstall would be to get a OEM Windows 7 Pro Microsoft Windows 7 Professional SP1 64-bit - Newegg.com

Follow up question: I'd like to sell this computer and buy something else. What do you think it's worth, assuming good/excellent condition?I believe at the time that I bought it in late 2010 it was worth around $800-900, and he sold it to me for $450

With a valid cope of windows 7 pro maybe $200.00 or less Lenovo ThinkPad Edge 13 13 3" 320 GB Intel Core 2 Duo 1 3 GHz 4 GB | eBay


Jerry

You're Welcome

How did you resolved your key issue?

Cool