Registry is not working

Question

RegistryKey autoStartOnConnKey = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon", true);
 
autoStartOnConnKey.SetValue(@"Shell", @"notepad.exe", RegistryValueKind.String);
 
MessageBox.show("done");
 

above code is working fine but there is nothing update in my registry.
i want to update shell with value notepad.exe
 
thanks .