Disablesyncsliderforsharedmailbox: !!top!!

Using Graph API requires registration in Azure AD and appropriate permissions.

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Set value to 0 or delete the key.

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Implementing DisableSyncSliderForSharedMailbox fixes this entirely. It ensures that when a team member maps a shared mailbox, they get the whole mailbox—every folder, every email, every attachment—from day one. disablesyncsliderforsharedmailbox