This error can happen when starting Mira. There are simple ways to resolve this as we moved to an OpenXR implementation and the active runtime needs to be set in order for the computer to know how to render the frames for the device.

Update the graphics card

  • Follow this link to update your graphics card driver
  • Restart your computer
  • Check that the error is still appearing

If you are an Oculus user follow this:

  • Open the oculus application on your computer
  • Click on the settings

  • Navigate to general and click on Set Oculus as Active in the OpenXR Runtime category.

If you are a Steam VR user (Valve, Vive, Pico etc...)

  • Open SteamVR
  • Click on the settings and then click on: Set SteamVR as Open XR Runtime

If you are a WMR (Windows Mixed Reality) user

If none of the solutions works follow this VERY CAREFULLLY

❗️

This requires administrator privileges, it should be taken as the last option available.

  • Open the Registry Editor as Administrator (right click and select
  • Navigate to \HKEY_LOCAL_MACHINE\SOFTWARE\Khronos
  • If no OpenXR exists create one by right clicking on Khronos and select New -> Key and name it OpenXR.

  • Open the OpenXR folder.
  • If no folder is named 1, create one by right clicking on OpenXR and select New -> Key and name it 1
  • Enter the 1 folder.
  • Right click and select New -> String value. Name it ActiveRuntime

  • Right click on that ActiveRuntime value and select Modify

  • Enter the value data depending on the runtime you use:
    • Oculus: C:\Program Files\Oculus\Support\oculus-runtime\oculus_openxr_64.json
    • SteamVR: C:\Program Files (x86)\Steam\steamapps\common\SteamVR\steamxr_win64.json
    • WMR: C:\WINDOWS\system32\MixedRealityRuntime.json
  • Create a New-> Key in this 1 folder and Name it AvailableRuntimes
  • Add a New -> DWORD (32-bit) Value and rename it depending on the runtime you use:
    • Oculus: C:\Program Files\Oculus\Support\oculus-runtime\oculus_openxr_64.json
    • SteamVR: C:\Program Files (x86)\Steam\steamapps\common\SteamVR\steamxr_win64.json
    • WMR: C:\WINDOWS\system32\MixedRealityRuntime.json

Now if you restart your computer you should be all set and Mira shouldn't crash anymore.