Some customers of the first year are still using basic authentication to connect with Microsoft 365 / Microsoft Exchange. On October 13th, 2020 Microsoft will entirely stop supporting this for Microsoft 365 due to obvious safety reasons. More info
Upgrading the Profile
Customers who are using the old Microsoft 365 / Microsoft Exchange connection will be presented with the warning as seen below when the Synchronizer admin logs in.
The admin can click on the ‘Upgrade Connection’ button themselves to go to the upgrade connection page
Wizard Microsoft 365
Microsoft 365 is detected due to 'outlook.office365.com' in the EWS URL, verify whether the upgrade is correct and press 'Upgrade'. After the upgrade a success message will be shown. The linked users need to re-connect to the calendar. The active users will receive an email asking to reconnect.
After the upgrade to Microsoft 365 IMPORTANT!
The ‘Link Users' page will show the following error for the customer’s admin user.