PeriopSim VR requires both the headset to be connected correctly, as well as SteamVR running properly. Check the following list for possible issues. If your symptom is not listed try restarting your computer or checking the setup instructions to make sure your computer is ready.
Check that all cables on the headset are connected and seated correctly. It is recommended to shutdown PeriopSim VR and Steam, disconnect the cables and reconnect them to ensure they are connected well. After re-connecting re-launch PeriopSim VR.
Check to see if the Windows Mixed Reality Portal is running. If it is not, click on the start menu and type in "Mixed Reality Portal" and run the app found. If it does not startup correctly, try re-starting your computer and then try again.
SteamVR should be running and show the an image of the headset and controllers connected and have a green coloured status message.
If SteamVR will not launch or is not found in the task bar, it could be stuck in a previous shutdown cycle. It is recommended to reboot the computer and try running PeriopSim VR to startup the software.
If the headset is not showing make sure that all connections on the headset are connected to the computer.
If running a Windows Mixed Reality headset ensure that the Windows Mixed Reality for SteamVR app is installed in Steam. See the setup instructions for more details.
If SteamVR shows a not ready message try quitting PeriopSim VR and SteamVR by closing their windows and then relaunch PeriopSim VR. If this does not resolve the issue reboot the computer and try again.