Try to change the privilege of server connected in Finder

Try to change the privilege of server connected in Finder. Here are my steps:

  1. Open Finder, click "Go", select "connect to server".
  2. After I connected to a server and the server itself is open for "read and write".
  3. Then the system generate a disk in Locations to the sidebar of Finder.
  4. Try to modify the files in the disk, but I find that I only have the permission to read.
  5. Checking the info of the disk, the info in "Sharing & Permissions" bar said that I can only read.
  6. Then I try to change the privilege from "Ready only" to "Read and Write" of the user I am using, but the system noticed "The operation can’t be completed because you don’t have the necessary permission".

I have no idea of how to change the privilege.