Need help doing a factory reset

Shaun98

Honorable
Mar 11, 2015
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10,790
Hi, I purchased a Asus laptop about a year or 2 ago and it came with windows 8 pre installed, Since then i have upgraded to windows 10 and then downgraded to windows 7. I have noticed that there is no product key on the base of the laptop however there is a square sticker that says windows 8 and has the windows logo on it.

What i am trying to do is re-install windows 8 and delete my current install of windows 7, But because there is no product key i am getting stuck when the windows 8 install is asking for one and there is no skip option.
If anyone can help that would be great, thanks!