Some or all identity references could not be translated.

why i m getting following error on server.  on local machine it working fine.

"Some or all identity references could not be translated."

my code is...

 public void GiveFolderPermission(string user)
        {
            DirectoryInfo myDirectoryInfo = new DirectoryInfo(@"D:\" + test);
            DirectorySecurity myDirectorySecurity = myDirectoryInfo.GetAccessControl();
            string User = System.Environment.UserDomainName + "\\" +
                                                           user.ToString();
            myDirectorySecurity.RemoveAccessRuleAll(new FileSystemAccessRule(User,
                                             FileSystemRights.Read, AccessControlType.Deny));
            myDirectoryInfo.SetAccessControl(myDirectorySecurity);
            MessageBox.Show("Permissions Altered Successfully");
        }