I have this problem and it is making me crazy. I have been banging my head for the last few weeks.
What I know:
This doesn’t have much to do with vorpX. It is a SteamVR issue. (Vive only)
To fix it, you need to run Steam as Administrator.
I just got vorpX yesterday and saw the error again. I started vorpX as Administrator, but not origin. I still got the error.
If there is a Vive/SteamVR tech-head out there, is there a better answer?
I will continue to work it and see if I can add anything later.