Hi @William Remezond ,
Will the same IMAP settings work in the classic version of Outlook? If it works, I suggest you switch back to the classic version of Outlook via the slider in the upper right corner.
Currently, 3rd party account (Gmail, Yahoo!, iCloud and other IMAP account) is still in development which means that it is not fully supported yet.
***With limited capabilities
And definitely, New Outlook is still working on product features development and improvement. In the future, more and more features will be released. You may check Microsoft Roadmap and keep monitoring the latest news:
Microsoft 365 Roadmap | Microsoft 365
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