How do I set up a DL4100 to mirror a site on a server?

I am setting up a small branch office for a European company. They keep most of the files that people need here on a Windows Server. Unfortunately, the latencies of both the connection and the server make working with the files directly slower than molasses.
I would like therefore to set up the DL4100 as a mirror site for the files. The files on the server would be synchronized from the server to the DL4100 once a day when both sides are likely not working on the files. It is really a one-way synchronization as the office in the US will get fresh data from Europe. The server in Europe is a Windows Server (not eactly sure what version). How can I set that up?
the idea is to once a day synchronize the files with those in Europe and only copy over the once that are new or have been updated. Possible?

your best bet is with a windows server and DFSR.

So, what’s a WD NAS good for?

A public file repository. Network Attached Storage. A large volume on the network that everyone has access to. You can also run some WD apps that will copy your pictures and documents from your PC to the NAS. If you have an Apple or Android phone you might also be able to view your media from afar.

You may also configure the NAS for RAID so if a hard drive dies it will keep on running. RAID is not a backup, it just provides “uptime”

It is hard to get Windows Server features from a free operating system.