If you have a Single Language install of Windows 8.1, then the add features option upgrades you to Windows Pro, for which you need to purchase a product key.
Since the product key in the new laptops comes built in in the bios
so I used on of the key finder software and I found the product key and copied it to the add features window but, it says that this key is not valid
so I understand that I have to purchase a new key if I want to upgrade
I thought it's extra features to the system !
Hi
There are 2 additional featues that you can add to Windows 8.1.
- If you have the standard version of Windows 8.1 you can upgrade to the Windows 8.1 Pro version.
- You can add the Media Center to Windows 8.1.
Both of these options require that you purchase a separate Product Key.
See the following article for answers to all of your questions.
Add features: FAQ:
http://windows.microsoft.com/en-us/windows-8/add-features-frequently-asked-questions
Regards