Secure file on PC and server

Hello

I have a Windows 2008 R2 file server in the main office. We are using DFS to access the files

I have a Windows 2008 R2 file server in the branch office and data are replicated using DFS (data a read/write mode)

User's laptops (windows 7) are configured to

• access files thru DFS closest site
• use offline files on these files

We need to secure files if the laptop and/or the branch office server are stolen. 

Data must not be readable by other people

It seems that EFS and DFS/DFSR are not compatible.

How can i do this ?

Thanks