I would try using a program such as the windows xcopy or this third party xxcopy that can be found here:
if your system does not have xcopy on it you can find it here:
I have also had luck with robpcopy from Microsoft which is located here: http://www.microsoft.com/Downloads/details.aspx?FamilyID=9d467a69-57ff-4ae7-96ee-b18c4790cffd
Any of these programs are great with large batches of files or large files there are switches on how to handle errors and what not.
What is the speed of the network you are transfering over? What is the Operating System?