Hi @André Léonard ,
Welcome to our forum!
Based on my test, i didn't find related settings to change root folder in New Outlook. If you need the feature, i'm afraid that you need to switch to Classic Outlook.
Please kindly understand that many functions are not designed at present. It is recommended that you could post the functions you expect and your sincere suggestions on the website dedicated to collecting feedback. We sincerely welcome your suggestions, and thanks for your understanding and support!
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