Using classic Outlook for Windows in business environments
Yes, unfortunately Bug Or intentional it looks like Microsoft is attempting to push us to use an outlook or live email address in order to get full functionality.
It also could just be a bug, As previously stated considering the email address that I'm currently using is a Gmail address.. however when you register for Microsoft services or when you register for Microsoft account you are given the option to create a new email address or use your current one, in this case when I created my Microsoft account I used my Gmail address instead of creating a new one ... So technically my Gmail address is my Microsoft account it's just not an outlook or live .com .....
I guess we will have to wait and see but for the meantime I have switched back to the old outlook because I absolutely cannot live without the task and reminder functionality ... It keeps me organized for business purposes.