I found if I used the same email address for the new Outlook Calendar as I used for Windows Mail all my events migrated automatically on setup. However there were flaws with the Outlook Calendar and I definitely did not want Outlook as my third party email carrier. So I downloaded "One Calendar" by Microsoft, and again had no problem with migration of my events. While Calendar One is not as good as Windows Calendar it is close and is a much better solution for me than their Outlook software. I then uninstalled Windows Calendar and Outlook from my OS. Microsoft made all of this an unnecessary (and they don't care) issue for all of us, but it turned out they had a solution in Calendar One that allowed me to ditch their pushy upgrade idea. At least for now, until they decide to take this away from me as well. Then I'll find another solution. And it won't be Microsoft.