Changing Folder Permission using C#

Question

Hi,

    I want to change folder permission from "Read " to "Write "/"Read " , I am working on IIS root folder on which resides on "C:\Inetpub\ftproot " . By default this folder comes with Read permission, but I am automating this using application, for which I need to enable Write permission for this folder by which clients connected to this FTP server can put there files.

  I tried few examples in MSDN, I am not still successful in enabling permission for the folder, I am working on a network domain , and the sample application provided works on "Domain Name" & "User Name" basis.

  I would like to resolve this issue, If you can provide me some pointers on this issue, it would be a great help for me to proceed ahead with project.  I would like to know if this folder permission can be enabled without using Domain & User Name parameters, I am afraid if this is the logic the application may file to work on a single system which is independent from network domains!

 I have attached my code below , I scanned my Domain Name and User Name and used in code , the code executed but write permission was not enabled.

using System;
using System.IO;
using System.Security.AccessControl;

namespace FileSystemExample
{
    class DirectoryExample
    {
        public static void Main()
        {
            try
            {
                string DirectoryName = @"C:\Inetpub\ftproot";

                Console.WriteLine("Adding access control entry for " + DirectoryName);
                // Add the access control entry to the directory.
                AddDirectorySecurity(DirectoryName, @"MYDOMAIN\MyAccount", FileSystemRights.Write, AccessControlType.Allow);
                Console.WriteLine("Removing access control entry from " + DirectoryName);
                // Remove the access control entry from the directory.
                RemoveDirectorySecurity(DirectoryName, @"MYDOMAIN\MyAccount", FileSystemRights.Write, AccessControlType.Allow);
                Console.WriteLine("Done.");
            }
            catch (Exception e)
            {
                Console.WriteLine(e);
            }

            Console.ReadLine();
        }

        // Adds an ACL entry on the specified directory for the specified account.
        public static void AddDirectorySecurity(string FileName, string Account, FileSystemRights Rights, AccessControlType ControlType)
        {
            // Create a new DirectoryInfo object.
            DirectoryInfo dInfo = new DirectoryInfo(FileName);

            // Get a DirectorySecurity object that represents the 
            // current security settings.
            DirectorySecurity dSecurity = dInfo.GetAccessControl();

            // Add the FileSystemAccessRule to the security settings. 
            dSecurity.AddAccessRule(new FileSystemAccessRule(Account,
            Rights,
            ControlType));

            // Set the new access settings.
            dInfo.SetAccessControl(dSecurity);

        }

        // Removes an ACL entry on the specified directory for the specified account.
        public static void RemoveDirectorySecurity(string FileName, string Account, FileSystemRights Rights, AccessControlType ControlType)
        {
            // Create a new DirectoryInfo object.
            DirectoryInfo dInfo = new DirectoryInfo(FileName);

            // Get a DirectorySecurity object that represents the 
            // current security settings.
            DirectorySecurity dSecurity = dInfo.GetAccessControl();

            // Add the FileSystemAccessRule to the security settings. 
            dSecurity.RemoveAccessRule(new FileSystemAccessRule(Account,
            Rights,
            ControlType));

            // Set the new access settings.
            dInfo.SetAccessControl(dSecurity);

        }
    }
}