Vive HMD or eye tracking related issues: HMD is not detected, not showing an image, not tracking etc.
a. Please refer to the setup instructions on the Vive Support page for more information and help using Vive VR: https://support.steampowered.com/steamvr/HTC_Vive/
b. Reboot your PC and the HMD and re-connect and check all connected cables first. Contact Tobii Support for persistent issues related to the eye tracking, such as no tracking or calibration issues.
c. Ensure the HMD is connected to the dedicated graphics card (on a desktop PC) instead of the on-board graphics card on the motherboard