Why isn’t my account syncing with Outlook 2016 on Windows?
At the moment, only personal Microsoft accounts using an Outlook.com domain are able to sync between Microsoft To Do and Outlook 2016. If your personal Microsoft account uses a domain such as @outlook.com, @hotmail.com, @live.com or @msn.com, then your tasks should sync automatically between Microsoft To Do and Outlook 2016 on Windows.
However, if you’re using a personal Microsoft account registered to a different domain, like @gmail.com or @yahoo.com, your to-dos won’t sync automatically. In order to sync your tasks between Microsoft To Do and Outlook 2016, you’ll need to a create a new alias for your account by registering a new outlook.com email address. To create a new alias, just do the following: