When launching 3D Vision Photo Viewer I get this error:
Stereo Error
NVIDIA 3D Vision features not enabled. Please review stereo setup information.
Press OK to launch NVIDIA Control Panel.
To fix this and enable 3D Vision Features, press OK, the put a tick in the Enable stereoscopic 3D box and run the Setup Wizard using the button below. These settings are found in the NVIDIA Control Panel under Stereoscopic 3D -> Set up stereoscopic 3D.
Your hardware must support the 3D Vision Features to enable them. In other words, you need a 3D monitor.