Two days ago I upgraded my macbook pro from 10.10 (yosemite) to 10.12 (sierra). The upgrade was pretty smooth but to upgrade it, I found many difficulties about my Apple ID.
Actually I have an Apple ID a long time ago but rarely use it. I remember to use it when I tried to install hackintosh. I tried to use it to download Sierra but I always got a complain on the AppStore like this ‘This Apple ID has not yet been used with the App Store. Please review your account information.’. I thought my Apple ID was deactivated somehow. not sure. Then I created a new Apple ID. But I got the same complain message. I tried many things like I said in https://discussions.apple.com/message/31865081#31865081 but none is working. Even I filled the payment form with my credit card. Finally it’s working. Somehow I tried to use my old Apple ID. It displayed the above message. Then I filled the payment form (the thing I didn’t do at the first time) with my credit card. This time my Apple ID is working and I can download and upgrade my OSX.