Dear Rowland; Thanks for the answer. I asked about joining a DC with file server because the previous post "File Server Recognize users and AD groups", the instructions that you gave me, helped set up the recognition of AD groups Folder permissions on the file server. But this file server was configured in a secondary DC. So, I created a file server only member of a domain. But I can not configure the folder permissions using AD groups. I will create another post in order to help with the problem. Grateful!