Open a level that contains instanced meshes (with built lighting) will crash the editor

UE - Graphics Features - Mar 19, 2015

Open a level that contains instanced meshes will crash the editor. Per the users description, the level must have had lighting built and then another level loaded or the editor restarted. Once the ...

Launching Android project to device results in Assertion Failed: AsyncLoading.cpp, Line 3710

UE - Platform - Mobile - Aug 31, 2020

After updating to 4.25.1 from 4.25 Packaged Android game crashes constantly with objects added to the map 4.25 Packaged game did not crash (editor did a lot but glad thats fixed in 4.25.1) Empty map ...

Linux editor can fail on start due to a stale TPS library in Engine/Binaries/Linux

UE - Platform - Linux - May 21, 2015

For 4.8, we moved LinuxNativeDialogs, a third-party library, to a different location (and also changed its API somewhat, so the old library is binary incompatible). However, some users apparently a ...

Shader compilation errors when packaging for iOS after disabling force full precision

UE - Platform - Mobile - May 29, 2024

User report: I want to run iOS shaders with half precision floats as I do on Android. If I disable Force 32 bits Floating Point Precision, there are unfortunately a bunch of shader compilation error ...

Crash when attempting to convert a sequencer actor into a BP Class

UE - Anim - Sequencer - Nov 15, 2016

Error message: Assertion failed: IsValid() [Link Removed] [Line: 752] Source Context: 738 return *this; 739 } 740 741 /** 742 * Converts a shared ...

This user's project crashes when instanced levels and the player pawn are unloaded and destroyed

UE - Gameplay - Jun 25, 2015

This user's project crashes when instanced levels and the player pawn are unloaded and destroyed. This occurs in the ProjectLevelGameMode Blueprint, in the Touched Finish Point commented area. This ...

Crash Importing some assets with "Keep Overlapping Vertex"

UE - Editor - Content Pipeline - Import and Export - Nov 29, 2016

Download offending asset here: [Link Removed] Error message: Assertion failed: NewPosition >= 0 [Link Removed] [Line: 452] Source Context: 438 virtual ~FFileHandleWindows() 439 ...

Slider Values are not working inside of a blueprint

UE - Gameplay - Blueprint - May 7, 2015

Slider Values are not working inside of a blueprint in 4.8 Preview 1. User Description: Problem with the numeric float/int boxes in the editor in Blueprints, if for example open the TPS Template a ...

Crash reimporting a skeletal mesh with less Material IDs than on first import

NOTE: Does not occur in 4.16, entered this to find a fix for licensee to integrate. Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 633] Array index out o ...

Raytraced Hair Lighting using Light Functions atlas and positions the Light function material doesn't render correctly

UE - Rendering - Graphics Features - Apr 9, 2026

Light functions don’t render on grooms when using ray traced shadows and positions in the light function material. The setup:A light (point/rect/spot) pointing to a groom hair system. The light's ...