Frustratingly, this has started giving the error (IShell Error -214702489 ...access denied) again.
I haven't even touched this code so I have no clue to why it keeps happening.
Also, I just discovered that this seems seems to work fine on some shortcuts and not on others.
You can't rely on any method, so far as I'm aware, as there are so many factors (including the requiring admin permission) which will cause this problem. Can I ask why you need to decode the link - there may be a better way of achieving what you're trying to do.