We have an outlook.com account with Office 365, but cannot get the Echo to link to this account.
The email address we are using is different but the calendar is the same as the office 365 account.
I can only get calendars that are linked to the registered email address, have you tried linking other calendars to your 365 one. or setting up a calendar with your registered email address and then linking that to the 365 one.
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