This parameter indicates that the share is a stand-in for another CIFS share whose location is specified by the value of the parameter. When clients attempt to connect to this share, they are redirected to the proxied share using the SMB-Dfs protocol. Only Dfs roots can act as proxy shares. Take a look at the msdfs root and host msdfs options to find out how to set up a Dfs root share. \otherserver\someshare