A:Answer Make sure you have your correct product. There is a difference between HOME and PERSONAL. If you used Home and changed it into personal you might want to delete the old version first. Also make sure you still provide the correct email address. Any changes will make it hard to install any Microsoft updates or products. Do not call a third party (INDIA) help center, they insist to control your computer and if not agreed on their virus scanner offer, they will put a Trojan virus on your PC.
Email or contact the USA Microsoft departments during the opening times. You can always go to Best Buy and let (for a small fee) the Geek Squad install it for you. Better prevent than cure.
Not knowing any specifics, I am sorry I cant do more than only advice you and direct you into the right direction.
Best Buy Costumer