RegistrySecurity Access is denied. C#

Question

I\'m currently having an issue when writing an app to set permissions on some Legacy keys. Legacy keys are quite locked down and to actually modify them in regedit you have

Answer 1

using System.Security;
using System.Security.AccessControl;
using System.Security.Principal;
using Microsoft.Win32;

First must Set a permission with right FULL-ACCESS to subkey

RegistryKey rkey = LocalMachine.OpenSubKey(_subKey, RegistryKeyPermissionCheck.ReadWriteSubTree, gistryRights.ChangePermissions);
if (rkey == null)
 throw new Exception("Not Open");
//-------
RegistrySecurity _registrySecurity =new RegistrySecurity();//Or rkey.GetAccessControl();
WindowsIdentity _windowsIdentity = System.Security.Principal.WindowsIdentity.GetCurrent();
RegistryAccessRule _accessRule = new RegistryAccessRule(_windowsIdentity.Name, RegistryRights.FullControl, InheritanceFlags.ObjectInherit | InheritanceFlags.ContainerInherit, PropagationFlags.None, AccessControlType.Allow);
_registrySecurity.AddAccessRule(_accessRule);
_registrySecurity.SetAccessRuleProtection(false, true);
 rkey.SetAccessControl(_registrySecurity);

//--------Now, Set owner

_registrySecurity.SetGroup(new NTAccount("Administrators"));  //This is optional
var SID = new System.Security.Principal.NTAccount("XXX\\Users");
_registrySecurity.SetOwner(SID);
rkey.SetAccessControl(_registrySecurity);

XXX : your account name