Hi @Peter , From the issue description, I understand that you wanted to hide/disable the archive button in new Outlook. To hide/disable the Archive button on the ribbon in new Outlook. Please follow the steps below:
In new Outlook, if you are using classic ribbon, switch to simplified ribbon.
Clik on 3 dots (...) at the right corner > select Customize > Uncheck the Archive button > Click on Save.
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