Abstractions.Windows.Security.RegSec C# (CSharp) Method

        public static Boolean RegSec(pInvokes.structenums.RegistryLocation where, string keyname, string username)
        {
            try
            {
                IdentityReference UserIRef = new NTAccount(String.Format("{0}\\{1}", Environment.MachineName, username));
                SecurityIdentifier UserSid = (SecurityIdentifier)UserIRef.Translate(typeof(SecurityIdentifier));

                using (RegistryKey key = pInvokes.GetRegistryLocation(where).OpenSubKey(keyname, true))
                {
                    RegistrySecurity keySecurity = key.GetAccessControl(AccessControlSections.Access);
                    string SDDL = keySecurity.GetSecurityDescriptorSddlForm(AccessControlSections.All);
                    //LibraryLogging.Info(SDDL);

                    foreach (RegistryAccessRule user in keySecurity.GetAccessRules(true, true, typeof(System.Security.Principal.NTAccount)))
                    {
                        //LibraryLogging.Info("registry ACE user: {0} {1} {2}", key.Name, user.InheritanceFlags.ToString(), user.IdentityReference.Value);
                        if (user.IdentityReference.Value.StartsWith("S-1-5-21-") && !user.IdentityReference.Value.Equals(UserIRef.Value))
                        {
                            //LibraryLogging.Info("mod registry ACE:{0} from unknown user:{1} to {2} {3} {4}", key.Name, user.IdentityReference.Value, username, user.RegistryRights.ToString(), user.AccessControlType.ToString());

                            SDDL = SDDL.Replace(user.IdentityReference.Value, UserSid.Value);
                            //LibraryLogging.Info(SDDL);
                            keySecurity.SetSecurityDescriptorSddlForm(SDDL);
                            key.SetAccessControl(keySecurity);

                            break;
                        }
                    }
                    foreach (string subkey in key.GetSubKeyNames())
                    {
                        if (!RegSec(where, keyname + "\\" + subkey, username))
                        {
                            return false;
                        }
                    }
                }
            }
            catch (SystemException ex)
            {
                LibraryLogging.Warn("RegSec:{0} Warning {1}", keyname, ex.Message);
            }
            catch (Exception ex)
            {
                LibraryLogging.Error("RegSec:{0} Error:{1}", keyname, ex.Message);
                return false;
            }

            return true;
        }