"Build All Levels" does not re-AddNavigationSystemToWorld

UE - AI - Navigation - Feb 28, 2024

The Build All Levels editor action cleans up the world's NavDataSet (UNavigationSystemV1::NavDataSet) as pre-rebuild world cleanup by calling: SetNavigationSystem(nullptr); inside UWorld::Cleanu ...

Exception on missing file during GC in horde storage

UE - Foundation - Horde - Storage - May 7, 2025

During GC, if a file was manually deleted (but the storage system is still track), GC can erroneously fail (and never remove the reference). This causes a backup in GC, putting the whole algorithm i ...

[CrashReport] UE4Editor_Renderer!FUniformMeshConverter::Convert()

UE - Graphics Features - Aug 3, 2017

This is a regular crash that has occurred through 4.16 and into the 4.17 previews. The callstack is similar to [Link Removed] (invalid), although the error message is different. User Description ...

Crash when destroying a geometry collection actor

UE - Simulation - Physics - Aug 7, 2020

When an actor with geometry collection is destroyed, the engine doesn't remove elements from array in the ChaosSolver So illegal references occurs. Removing element with following quick fix code ...

Launching QAGame for HTML5 creates an 'uncaught exception: out of memory'.

UE - Platform - Mobile - Jan 18, 2017

Launching onto HTML5 opens the browser to Uncaught Exception: out of Memory After running it on a 64-bit browser, the following is printed:uncaught exception: abort("Cannot enlarge memory arrays. E ...

[5.4+] World Partition Landscape Spline Meshes Builder - Source landscape splines are not properly removed/hidden

UE - World Creation - Worldbuilding Tools - HLOD - May 30, 2025

LandscapeSplineActors and LandscapeSplineMeshesActors are not behaving as expected in 5.4 or 5.5. Testing in 5.4 the issue mostly seems to stem from issues with the Target Landscape -> Landscape Ac ...

Crash when changing a Play Node's "Sequence" to a Montage

OLD - Anim - Jan 20, 2016

I understand that this is not something you're intended to be able to do (Montages aren't used this way), but we should bar the user from inserting a montage into this variable slot. Crash occurs w ...

[CrashReport] Mac crash - libobjc.A.dylib!objc_retain() [UnknownFile]

UE - Platform - Apple - Nov 10, 2017

This is a longstanding but low frequency Mac crash. User DescriptionsChanging camera shake values and testing in a new editor window Callstack from Log[2017.11.09-19.23.22:392][ 63]LogMaterial: Mi ...

Open Level Crash in Gear VR

UE - Platform - XR - Oct 5, 2016

Projects using Open Level (blueprints) or ServerTravel (in C++) will crash the application once it's open on a device using Gear VR Mode. 10-05 18:01:46.451: A/art(19619): sart/runtime/check_jni.cc ...

Using a Macro to access a variable from another Actor causes a crash in Standalone

UE - Gameplay - Blueprint - Jun 8, 2015

Using a Macro to access a variable from another Actor causes a crash in Standalone. This does not seem to affect any other preview in editor, nor packaged games. Reproduced in 4.7.6, 4.8 Preview 4, ...