Recovering lost product key

[drahul1nene]

I bought new pc and it had pre-installed windows 10 and it all needed an activation.
So I handed it to computer analyst,
But he unknowingly installed windows (that too a copied version)and thus I lost my pre-installed version of windows 10.Is ther anything I can do to recover my
activation key or product key of windows 10?

 

[Colif]

Did you get any documentation when you got PC? If it had Win 10 installed you should have got a piece of paper with the code on it. What brand PC is it?

they used to attach the codes to sides of machines or inside (depends on maker).

Why did he reinstall windows? Why did you give it to him before activating? What was he doing to it?