How to I install and activate Mathematica on my personal comptuer?
Staring on 11-7-2022 you will now need to activate Mathematica with your Office 365 (MavMAIL) account. Also if you previously had been using an activation code the next time it comes up for activation you will need to switch to using your Office 365 account. You will probably also want to upgrade to the latest version so you can get the latest features and any bug and security fixes as well.