A. You can direct Outlook clients to use a RODC by setting the DS Server registry value. Setting the value will make the Outlook client use an RODC that's a Global Catalog for Global Address List and other processes.
To force the client to use the RODC, set the registry value HKEY_CURRENT_USER\Software\Microsoft\Exchange\Exchange Provider\DS Server to the Fully Qualified Domain Name of the global catalog server that you want Outlook to use.
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