Unreal Engine Issues
Unreal Engine Issues
Exception generated launching Horde Agent built with 5.6
UE - Foundation - Horde - Server - Jul 28, 2025The source of the problem seems to be using IOptionsSnapshot with a Singleton. Per the MS documentation for IOptionsSnapshot, "Is registered as Scoped and therefore can't be injected into a Singleto ...
'Malformed sequence hierarchy' ensure hit after modifying sub-sequence tracks
UE - Anim - Sequencer - Sep 5, 2025It's possible for there to be multiple instances of the same sequence in the evaluation states cache if the same sequence is used in multiple sub-sections. Caches are never removed from the evaluat ...
FRuntimeFloatCurve in datatable causes editor crash
UE - Editor - Apr 24, 2024Inside SCurveEditor::ZoomToFitHorizontal and SCurveEditor::ZoomToFitVertical, the program navigates through a TArray<FRealCurve*> called CurvesToFit in a for each loop. Inside the for loop, if the p ...
Access Violation in delegatesignatureimpl.inl after HotReload
UE - Foundation - Core - Jan 27, 2017This is the third different callstack in an attempt to repro a HotReload crash I am experiencing. The other two are:[Link Removed]: Nullptr Ensure and crash after HotReloading[Link Removed]: Assert ...
Deleting the code files for a custom component from a project will result in an Engine crash when trying to open any Blueprint using that component.
UE - Gameplay - Blueprint - Feb 20, 2015Adding a custom component to a Blueprint and then deleting the code class defining that custom component from the project will crash the Editor any time you try to open a Blueprint containing that c ...
Data Tables with 'ParticleSysParam' structs cause crash
UE - Niagara - Feb 4, 2019Data Tables with 'Particle Sys Param' structs in them as variables will crash when opened. ...
Origin Shifting Landscape crashes Render Thread
UE - LD & Modeling - Terrain - Landscape - Jan 10, 2020Shifting the world origin with a landscape in the level causes a crash in the render thread. This does not crash in 4.23.1 (CL-9631420). This was reported and tested in 4.24.1 (CL-10757647) and rep ...
Crash occurs when diffing blueprint that has had one of its variables changed to a Soft Object Reference
UE - Gameplay - Blueprint Editor - Oct 3, 2017A crash occurs when diffing a blueprint that contains an array that has changed from an Object Reference to a Soft Object Reference. Note: I figured that this could be related to another bug that I ...
Editor crash when opening Project Settings on Linux
UE - Platform - Linux - Mar 29, 2017When the Project Settings is opened on Linux, a call is made to run an iOS-related C# program (execute iPhonePackager certificates). This call causes the editor to crash. Unable to find mention of ...
Android build fails with GPU Lightmass plugin enabled
UE - Platform - Mobile - Nov 5, 2020Packaging for Android fails with the GPU Lightmass plugin enabled. A customer reported this and I was able to successfully repro it, however my callstack was different. I'm attaching my logs and cal ...