I downloaded the demo version of Office 365 on my new MacBook and it’s telling me that my subscription has expired and I need to activate it. I have a product key, but can’t figure out where to type it in. It used to be simple in software land: You bought a program, installed it and you were done. Then we added product keys because people would buy one copy of a program and install it on dozens of systems, friend’s computers, school, etc. That was still built around the basic concept of you buying ownership of the software: one you’d entered the registration code you were able to use that program forever if you so desired. In the last few years, however, the ownership model has changed significantly with computer software and now we are paying for a subscription service, a lower fee that gains us access to the program so long as we keep paying it. This started with anti-virus programs on the Windows PC side where they’re only useful if the company keeps updating the virus definitions even long after you’ve paid and installed their program.