Startup Crash Fix: Assertion failed: ExternalPooledTexture.IsValid

I couldn’t open my recent project. It crashed on startup with this error:

Assertion failed: ExternalPooledTexture.IsValid() [File:D:/build/++UE5/Sync/Engine/Source/Runtime/RenderCore/Private/RenderGraphValidation.cpp] [Line: 254] Attempted to register NULL external texture.

After removing my “saved” folder, everything worked again.
I nailed the error down to the following setting:

File: ProjectName\Saved\Config\WindowsEditor\EditorPerProjectUserSettings
Line:
PerInstanceSettings=(ConfigName=“FourPanes2x2.Viewport 1.Viewport1”,ConfigSettings=(ViewportType=LVT_Perspective,PerspViewModeIndex=VMI_Unlit,OrthoViewModeIndex=…

Fix:
Setting the “PerspViewModeIndex” from “VMI_Unlit” to “VMI_Lit” →
PerspViewModeIndex=VMI_Lit

Hope this helps someone google this issue =)

ps: I already sent the bug report using the crash-formular, can I report it elsewhere (for UE5 specificly)?

Edit: For the devs: I think it has something to do with showing the lumen scene and setting the viewmode to unlit. Saving and closing the project with this settings could be the cause of the crash

Engine: Public UE5 Early Access 2 (no git built version)

1 Like