UE5.7.1 Crashing After Inserting Older Version Asset

Development Programming & Scripting
1

Hi

I, probably rather stupidly, added an older version asset bought from FAB, (UE5.4) to the project. The Project is UE5.7.1. Since adding that asset, I can open the project, but it then crashes shortly after.

I have removed the asset from the file, but it still keeps crashing.

The last line in the log is;

[2026.01.16-13.25.05:672][725]LogWindows: Error: appError called: Assertion failed: Scene->RayTracingScene.GetCachedInstanceGeometry(RayTracingInstanceIndexMain) == CachedRayTracingGeometry->GetRHI() [File:D:\build++UE5\Sync\Engine\Source\Runtime\Renderer\Private\PrimitiveSceneInfo.cpp] [Line: 395]

On the Epic Games help it suggested deleting the following folders from the Project File, which I did.

  • DerivedDataCache
  • Intermediate
  • Saved

It still crashes shortly after opening the project.

Any help would be appreciated.

Kind regards

Mike

2

Do you have a C++ project so that you can run the project in debug from Visual Studio? VS should trigger a breakpoint if you do. You should (hopefully) be able to backtrack the callstack to find which asset and primitive is the culprit.

PrimitiveSceneInfo.cpp:395 is inside FPrimitiveSceneInfo::IsCachedRayTracingGeometryValid. Each FPrimitiveSceneInfo is associated with a component.

This seems to happen in a ray tracing path.
`RayTracing.cpp → GatherRelevantStaticPrimitives → ParallelForWithTaskContext → checkf(SceneInfo->IsCachedRayTracingGeometryValid()…)`

Maybe disable raytracing and/or Nanite in the project and resave whatever maps/assets is related to the marketplace asset and re-enable those again. This could be because of serialized data, but I am only guessing.

3

Hi

Many thanks for the reply.

I do not have a C++ Project.

I have deleted the Imported Asset from the Content folder, along with all its associated Textures.

I will try disabling Ray Tracing and Nanite.

The programming stuff it quite a bit above my head.

Mike

4

Tried Disabling Ray Tracing and still crashes.

At this moment tempted to bin this off and revert back to Twinmotion. Many hours spent on this and seem to be back to square one.

The programming stuff is way beyond me so have no idea where to start.

Mike

5

Do you by any chance start the project in the editor with a default map that previously referenced those assets? If so, in editor preferences (from any other project), set Load Level at Startup to None. This should ensure that you do not open any map on startup. If it doesn’t crash after you have done this, then it is likely you have old data still in the map related to those assets.

Edit*
I maybe recall wrong about editor settings being global. You should have a file called EditorPerProjectUserSettings.ini with a section in it where you can set this:

[/Script/UnrealEd.EditorLoadingSavingSettings]
LoadLevelAtStartup=None

6

Thank you @Denny

I’ll have a look at this.

Mike

7

It was a blank project to start with. The problem only occurred when I imported the old 5.4 asset.

Mike

8

OK. Opened the Project and changed the Startup Level to None and Saved All.

Opened ok. It happens when I navigate around the scene. It lets me move around a bit, then freezes and crashes.

Mike