Choose the network connection you will be using (Internet or Local Area Network). 

For Internet connections, cache is not used, because data transfers appear to hang, although they are just happening too slowly to see results for long periods of time.

If you want to transfer files over a local area network at the highest possible speeds, be sure that  that the Network is Local Area Network, that the Compress Files and Encrypt Files boxes are not checked, and that cache (use the Edit menu to choose Preferences) is enabled.