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> What would be the best way to combine directory-based encryption with OneDrive/SharePoint/Cloud funcktionality?
Currently OneDrive's own encryption is used to protect shared files.
I want to give you some suggestions, but I do not find any Microsoft official documentations to to describe this issue. Thanks for your understanding.
To help you better, it's best to open a support ticket with Microsoft Support to help review your problem and help you test remotely.
> Are there settings or is it somehow possible to ban all network communication of the Office Products without losing basic functionality?
Could you please tell us which actions does "Office Sync and Connected Experiences are deactivated" point to?
From an Office perspective, please refer to "(This feature has been disabled by your administrator) error in Microsoft Office", and try to configure the specified registry values under Cause section.
UseOnlineContent --- Value: 0
SignInOptions --- Value: 3
But please note, if you are running Microsoft 365 apps, I do not suggest you set values for SignInOptions to be 1 or 3.
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