Overview
You have created a new profile with the Microsoft 365 connector.
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You will notice an error message after logging in into O365 Microsoft 365 and after allowing the permissions.
"Cannot determine e-mail address for O365Microsoft 365", see below
Solution
Most likely you are using an Microsoft 365 subscription which is not supported, as this plan does not have the Exchange Online component, more info on our requirements.
Compare the Microsoft 365 Business plans here.