I’m working on a project in Unreal Engine 5.4 and trying to build lights on a Nanite-enabled landscape. However, I’m encountering an error that I haven’t been able to resolve, even after rebuilding the level from scratch. The error details are as follows:
Assertion failed: ExportSettings == *ExistingExportSettings [File:D:\build++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\Lightmass\Lightmass.cpp] [Line: 546] Attempting to add the same material twice with different export settings, this is not (currently) supported
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The error mentions that it’s trying to add the same material twice with different export settings, which Lightmass apparently doesn’t support. I’ve tried creating a new level, re-adding the Nanite landscape, and reapplying materials, but I keep facing the same issue.
Has anyone else encountered this, or does anyone have insights into how to troubleshoot this problem? Any suggestions would be much appreciated!