Failed to luanch .....exe. Exit code: 512

Greetings. I have a bundle which requires hardware drivers. To install them I've copied the driver files to a folder on the local machine. I then have an install action to launch the executable. The installer .exe has a silent switch /S which I've put in the Command line parameters. When the bundle is run the Launch executable action throws a failed to launch Failed to launch path to exe. Exit code: 512.

If I take the switch out of the Command line parameters the exe does launch but then I've lost my silent install.

I've used this approach many times before without problem. I've tried about a million things, still no luck. Any help would be much appreciated.