Jeromee

Problem solved. The cause was I have installed on my PC both HTC Vive Streaming Hub and Oculus Desktop environments, meaning two OpenXR runtimes that may conflict with each other: - C:\Program Files (x86)\VR\Steam\steamapps\common\SteamVR\steamxr_win64.json (for VIVE) - C:\Program Files\Oculus\Support\oculus-runtime\oculus_openxr_64.json (for Oculus) In this situation, this OpenXR runtime path must be assigned...: - not only to the 'HKEY_LOCAL_MACHINE\SOFTWARE\Khronos\OpenXR\1\ActiveRuntime' registry key - but also to the 'XR_RUNTIME_JSON' environment variable The second point was the missing point for me.

The two Unreal 5.1.1 projects below (set up with ViveOpenXR_1.6.0.r2 plugin) launch well to a connected XR Elite, via the VR Preview of UE Editor. However the resulting Windows target build (a Windows EXE) does not launch to the connected XR Elite. It only launches in a desktop window. Concerned projects: - 'ViveOpenXR_1.6.0.r2_UE51_Project' sample OR - Epic VR Template 5.1.1 with 'ViveOpenXR_1.6.0.r2_UE51_Plugin' Configuration: - XR Elite software: VR 1.0.999.350 - SteamVR 1.26.3 with OpenXR runtime = 'SteamVR' - VIVE Streaming Hub 1.1.8, via USB VIVE Streaming Cable, OR via Wifi 6E Log output by the Windows app