Open registry and add new key
Key: HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Search
Value name: DisableServerAssistedSearch
Value type: REG_DWORD
Value: 1
Open registry and add new key
Key: HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Search
Value name: DisableServerAssistedSearch
Value type: REG_DWORD
Value: 1