Recently a friend of mine asked about how to share a folder located in a Surface RT. Something that I have to confess a have not had tried in my Surface. After a little research on line I found that the Surface RT has by default the server service disabled but the good news is that is there and it can be enabled if you want. So that's the first thing to do. Open the services application and Start the Server Service.
Once the setting is activated you need to check that you have the capability of Sharing files and printers activated in your Surface RT.
After that you are ready to share any folder and map it in any of your PCs gaining access to your Surface RT folder after providing the proper user name and password.