RegistryKey currentUserX64View = RegistryKey.OpenBaseKey( _
                  RegistryHive.CurrentUser, RegistryView.Registry64);
 
                RegistryKey key = currentUserX64View.OpenSubKey(keypath, _
                  RegistryKeyPermissionCheck.ReadWriteSubTree);
 
                if (key != null)
                {              
                    key.DeleteSubKeyTree(keypath);
                    key.Close();
                }