Unreal Engine Issues
Unreal Engine Issues
Sequencer frame range progression is not continuous
zComponent - Archive - Oct 28, 2021The end of the level visibility section places a DeterminismFence. This causes the issue. The fence clips the frame range and produces a discontinuous frame ranges, e.g. 23201~24000, then 24001~24 ...
Camera behavior during "Orbit Pan Mode" (Alt+MMB+Drag) is wrong while piloting an actor
UE - Editor - Nov 18, 2025In the Level Editor, dragging the mouse while the "Alt" key is pressed performs one of the "Orbit" movements: OrbitRotation, OrbitPan, OrbitZoom. The same can be done while Piloting an actor. Howev ...
LogHttp:Warning: 0000024E4A050880 Response Header Content - Issue with the Survey
Tools - Feb 28, 2017LogHTTP:Warnings are populating in the output log when the editor opens any project in 4.15.1 This is not occurring in //UE4/Main This is not occurring in 4.14.3 Marking as regression WarningsLo ...
Crash in GC - FSharedStruct reachability race condition
UE - Core - Systems - Jul 13, 2026This Jira was created from the linked EPS case: =============================================== This issue is caused by FSharedStruct batching reachability requests to the same underlying FInstan ...
Crash on garbage collection - Encountered 20 object(s) breaking GC Clusters assumptions.
UE - Foundation - Core - Aug 15, 2018Garbage collection crash during opening cinematic. Note after crashing and relaunching the game the saved file appears as 8% complete instead of 0%. Note this crash is also occurring with //UE4/D ...
[CrashReport] UE4Editor-Core.dylib!FTextHistory::Rebuild(TSharedRef<FString,()
UE - Platform - Apple - Aug 15, 2017This is a trending Mac crash in 4.17.0 that has also occurred with some frequency since at least 4.14. I have not been able to identify any matching callstack occurring on Windows, although it does ...
VerboseCookerWarning warnings: Saving object into cooked package %s which was created at cook time, Object Name UniqueObjectNameForCooking_0, Full Path %s, Outer class %s
UE - Core - Data Pipeline - Cooker - Jun 19, 2023Creating objects at cook time that are exported into the cooked package is a possible cause of indeterminism, and therefore we have banned it in engine classes and will fire a warning about it. Cur ...
Level Instance Property Override: Actor::Tags overridden pre-CS but clobbered by RerunConstructionScripts with no post-CS re-apply
UE - World Creation - Worldbuilding Tools - May 4, 2026Summary When using the Level Instance Property Override system, overrides applied to `AActor::Tags` are silently lost for Blueprint actors whose Construction Script assigns or appends to `Tags`. The ...
Per object shadows, Error: FMatrix::InverseFast(),
UE - Graphics Features - Nov 13, 2015LogUnrealMath:Error: FMatrix::InverseFast(), trying to invert a NIL matrix, this results in NaNs! Use Inverse() instead. LogOutputDevice: === Handled error: === Ensure condition failed: false [File: ...
[CrashReport] UE4Editor-CoreUObject.dylib!UPackage::Save() during COTF
UE - Foundation - Core - Cooker - Nov 21, 2017This is a common Mac crash that has occurred since at least 4.17.1 User DescriptionsJust trying to launch my project on any output I can. No luck.launching AR project on IOS device. Ugg. Last adjus ...