Unreal Engine Issues
Unreal Engine Issues
This Blueprint will not compile and causes a crash in 4.8
UE - Simulation - Physics - Mar 18, 2015The MiningBuilding Blueprint in this user's project will not compile. Clicking the compile button never switches it to "Good to Go", and a warning that it needs to be compiled appears at PIE. Repro ...
[CrashReport] Assertion on Mac: Could not create a libwebsocket - FNetworkFileServerHttp::Init()
UE - Platform - Mobile - Jun 22, 2017This is a common crash on Mac that occurs in the 4.16 release. This appears similar to [Link Removed], which was closed with the 4.13 release. Users have not provided descriptions. Many (but not a ...
[CrashReport] UE4Editor_LevelEditor!FLevelEditorActionCallbacks::Paste_CanExecute() [leveleditoractions.cpp:1602]
UE - Gameplay - Blueprint - Jan 17, 2017This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Assertion failed: GEditor->GetSele ...
Replicated components spawned by CreateComponentOnInstance are broken by object reuse
UE - Gameplay - Apr 5, 2023When the gameplay framework component manager creates components as part of CreateComponentOnInstance, it passes in the requested class name as the literal name of the component instead of using the ...
DOF - TAA pass ghosting when using r.DOF.TAA.CoCBilateralFilterStrength
UE - Graphics Features - Aug 7, 2025In Unreal 5.6, there's a new CVar: r.DOF.TAA.CoCBilateralFilterStrength, which should help with ghosting artifacts introduced by TAA in DOF passes. However, it doesn't work as expected since many gh ...
Crash Importing Skeletal Mesh LODs with a lot of morph targets
OLD - Anim - May 18, 2016Crash Importing Skeletal Mesh LODs with a lot of morph targets Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 785] Array index out of bounds: 2 from an ar ...
Users project crashes when opening level that loads multiple sub-levels
UE - Foundation - Core - UObject - May 31, 2017Users project crashes when opening level that loads multiple sub-levels. Unable to reproduce this in a clean project so the users project is provided though Epic's box account (link is in the repro ...
Inconsistent behavior with spawned actors when Play, Pause, and Stop are called in a Level Sequence Player
UE - Anim - Sequencer - Feb 15, 2017This is a report about three different issues that are tightly related to each other, so I decided to include them in a single report. The behavior of actors spawned by a Level Sequence Player is no ...
Importing through Python fails
UE - Editor - Content Pipeline - Import and Export - Feb 20, 2019Version 4.21:The script result in popping the Alembic Import windows instead of a silent importThe provided options are ignored by the importer. Version 4.22: Results in the provided callstack wi ...
The pak file specified in PakFileRules is not created correctly
UE - CoreTech - Aug 8, 2023The rules by which chunks are created are ambiguous and currently do not ensure that both PakFileRules and PrimaryAssetLabel settings are reflected. In this sample, depending on the PrimaryAssetLabe ...