Hey there!\n\nI have just recently reinstalled Windows 8.1 on my laptop which a friend gave me a install DVD. But there is one problem, it is for Windows 8.1 Pro, which I do not have a product key for. I did install it using the generic key provided by Microsoft. Most likely it wont last forever which I don't want. I do however have a Windows 8 Core key which was integrated into my laptops BIOS but I want to put it on my Windows 8.1 Pro installation. Is it possible or should I simply resort to other methods?\n\nThanks!