EDIT: Curiously fixed only by updating my driver 
Hey, I’ve just installed UE 5.5 and created a new project using the “Game > Third person FPS” project template. Left everything at default, except “Include starter pack”, which I unchecked.
When I try to load the project, I get this error:
appError called: Assertion failed: SizeInfo.ResultSize != 0 [File:D:\build++UE5\Sync\Engine\Source\Runtime\D3D12RHI\Private\D3D12RayTracing.cpp] [Line: 2849]
Unexpected acceleration structure buffer size (0).
Geometry initializer details:
DebugName=PlanarReflectionPlane NumSegments=1 NumPrims=2048 IndexStride=2
I’ve seen another post with the same error, and other similar ones where people suggested to disable DX12 and switch to DX11 for the project, but that’s not a valid workaround for me as I want to use DX12 features in this project.
My system specs:
Windows 11 24H2
AMD Ryzen 9 7950X3D
NVIDIA RTX 4090
GeForce Game Ready Driver 566.03