Do you have a COA (certificate of authority) on the side of the computer case? This will give you a serial number. If you do have one the computer seller usually gives you a recovery disc with it. (which you can still ask for)
If you don't
have a COA you have an illegal copy of windows on your computer. You can buy computers without windows, however if it is already installed it must have a COA with it. It is illegal to sell a computer with Windows installed but without the COA.
Mitz
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