Hi,
I have Windows 8.1 Single Language in my laptop. I did "Uninstall everything and reinstall windows" in my laptop. After that, my orijinal windows started to do not work. It says "Activate Windows." But I can not activate it because it also says "This product key does not work." It is my only and orijinal product key. I had bought it with my Casper laptop years ago.
I do not understand why this problem happened. How can I solve it? I do not want to pay for a new product key. It does not have to be necessary. Please help and solve this problem.
Thank you.