Delete SteamVR folder and remove all OpenVR packages in package manager. Then install. If there are errors reported after installation you may need to reimport the project. This release will ...

With the final launch of the HTC Vive now in sight, Valve is preparing developers for virtual r eality technology by bringing native SteamVR support to the Unity game engine, absent an apparent price ...

This should not be called, because the device index is non-deterministic, and, though 1 may work in some cases, won't work in all. The index changes based on device assignment of the system.