How to install Windows 7 to repaired Desktop

[Geek-9pm]

My old Dell Desktop had a bad CPU. Somebody put in  the wrong CPU chip for that motherboard.  I had installed Windows 7 Pro before I found the mistake. I replaced the CPU.

Now I have erased the hard drive and tried to install Windows 7 again. Well, the install was OK. But I can not verify the COA that goes with this  Windows 7. It worked before, several months ago, but now I can not use it.

My guess is the CPU replacement changed some kind of ID thing.
Is thee a way to ask Microsoft to reverse identify a CPU?

[patio]

Yes.
Call their 800# and explain what's transpired...they will issue a new key...

[Geek-9pm]

Thanks Patio. Will do.
Is this the right number for USA?
https://support.microsoft.com/en-us/gp/product-key-does-not-work/en-us
Product Key is missing or not working

[patio]

Yepper...