Epic's GPUlightmass

HELP ME:(

Getting crash error when using UE 4.26 preview1 GPU Lightmass


Fatal error: [File:/Build/++UE4/Sync/Engine/Source/Runtime/Windows/D3D11RHI/Private/D3D11Util.cpp] [Line: 258] Direct3DDevice->CreateComputeShader((void*)CodePtr, CodeSize, nullptr, Shader->Resource.GetInitReference()) failed at D:/Build/++UE4/Sync/Engine/Source/Runtime/Windows/D3D11RHI/Private/D3D11Shaders.cpp:286 with error E_INVALIDARG

UE4Editor_D3D11RHI
UE4Editor_D3D11RHI
UE4Editor_D3D11RHI
UE4Editor_D3D11RHI
UE4Editor_RenderCore
UE4Editor_RenderCore
UE4Editor_RenderCore
UE4Editor_GPULightmass
UE4Editor_GPULightmass
UE4Editor_GPULightmass
UE4Editor_Core
UE4Editor_Core
UE4Editor_RenderCore
UE4Editor_RenderCore
UE4Editor_Core
UE4Editor_Core
kernel32
ntdll


Inside Project setting - “Default RHI” option is not visible in my editor.

I am Using GTX1060 card