There's two problems here. The target platform and the command.
With Windows 8 it works for me
It only works on Windows 8 because it's a new feature in Windows 8. Previous versions don't have anything mapped to that GUID.
eg if you try using something which is supported in previous versions like the classic 'god mode':
shell:::{ED7BA470-8E54-465E-825C-99712043E01C}
works fine,
shell:::{F6B6E965-E9B2-444B-9286-10C9152EDBC5}
will give you an error message.
Secondly, you're leaving out the shell:::
prefix when you call Process.Start()
. It should look like:
Process.Start("shell:::{F6B6E965-E9B2-444B-9286-10C9152EDBC5}");