Hi @Piero ,
Welcome to our forum!
As i know:
Outlook supports Modern Authentication in all current Microsoft 365 subscription SKUs and Outlook 2021 LTSC (any SKU with build 11601.10000 or higher) when connecting directly as Outlook.com. If your Outlook is configured to connect to Outlook.com using POP or IMAP, Modern Authentication is not supported.
Looks like you are configuring your Hotmail account as POP, please try to create a new Outlook Desktop profile(Control Panel>Mail>Show Profiles>add) and then add your Outlook.com account using automatic account configuration.
More information: Modern Authentication Methods now needed to continue syncing Outlook Email in non-Microsoft email apps.
Hope to help you!
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