Crash (Assertion failed "SystemInstanceController->IsSolo()") when enabling "Start with Tick Enabled" on a Niagara Component

UE - Niagara - Oct 17, 2024

Currently, Niagara Components are only expected to have their TickComponent() method called when their system is marked as "Solo", which makes them be simulated individually. In the most common scen ...

Editor Crash with corrupted asset when opening within level or via the content browser.

Tools - Jan 5, 2017

Editor will crash when a skeletal mesh has been added to a level and then reopening the project later if you try and access this level. If you attempt to open the skel meshes in the content browser ...

Crash when exiting editor before EditorUtilityTask completes

UE - Editor - UI Systems - May 29, 2024

If exiting the editor before the EditorUtilityTask completes, it crashes. It will not crash if canceling the UtilityTask and then exit the editor. The following implementation does not allow destruc ...

[CrashReport] UE4Editor_CoreUObject!PackageReloadInternal::LoadReplacementPackage() [packagereload.cpp:274]

Tools - Aug 17, 2018

No user comments in crash group 262 UPackage* LoadReplacementPackage(UPackage* InExistingPackage, const uint32 InLoadFlags) 263 { 264 if (!InExistingPackage) 265 ...

VisualizeTexture with the BMP flag causes a crash when any mip over mip0 is requested

UE - Rendering Architecture - Dec 18, 2024

When a mip level higher than 0 is requested in VisualizeTexture, the engine will crash. The root cause appears to be VisualizeTexture.cpp:924, on which an incorrect mip level is used to read a non-m ...

Rendering sequence with livelink data has issues with smooth engine offset

UE - Virtual Production - IO - LiveLink - Apr 26, 2023

[Link Removed] for reference Playing back a sequence shouldn't have buffered samples. We should have a single one, which was built from the sequence. We need to make sure when played back that it ...

Global SkyAtmosphere and Clouds Issues (Ambient Light)

UE - Graphics Features - Dec 3, 2024

Ambient Light on Volumetric Clouds from Sky Atmosphere always is calculated as if the clouds are at the north pole of the planet. Using a sphere-shaped Sky Atmosphere and Volumetric Clouds causes t ...

Crash Duplicating an empty AtlasRow material node

UE - Rendering Architecture - Materials - Nov 29, 2023

This isn't a hard crash, but a "verify(...)" from MaterialExpressions.cpp, line 559. ...

Deadlock in UAnimationSequencerDataModel::Evaluate where FScopeLock Lock(&EvaluationLock) blocks execution indefinitely

UE - Anim - Nov 4, 2025

When both the Sequencer Editor and an Animation Curve Editor are open for the same animation asset, the editor freezes completely upon editing the curve. Analysis indicates that the freeze is caus ...