Unreal Engine Issues
Unreal Engine Issues
Crash on iOS9 when using Apple's CFNetwork library
UE - Platform - Mobile - Dec 6, 2016Many clients have hit a crash due to an Apple library using operator delete on a memory block that was not allocated with operator new. This happens with the following callstack on iOS9 in UE4.13 o ...
Users are unable to create projects when the default project location is a networked drive
UE - Editor - Workflow Systems - Oct 23, 2024There have been multiple reports of this issue, particularly from schools, over the last 10 years:https://forums.unrealengine.com/t/invaild-folder-path-with-network-user-drives/283475https://forums. ...
Changing a Media Player asset from Stream Mode: FromURL to From Memory crashes the editor
Tools - Dec 30, 2014Changing a Media Player asset from Stream Mode: FromURL to From Memory crashes the editor. In 4.8, the editor crashes immediately upon changing that value, with no crash report. In 4.6 and 4.7 Pre ...
BuildPatchTool crashes on Mac and Linux when building android or ios with multiple chunks
Portal - Feb 18, 2020"It seems that deallocation of TLazySingleton<FInternationalization> causes unhandled exception. If DISABLE_LAZY_SINGLETON_DESTRUCTION=1 is provided - the build completes successfully" ...
"Build All Levels" does not re-AddNavigationSystemToWorld
UE - AI - Navigation - Feb 28, 2024The 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, 2025During 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 ...
[5.4+] World Partition Landscape Spline Meshes Builder - Source landscape splines are not properly removed/hidden
UE - World Creation - Worldbuilding Tools - HLOD - May 30, 2025LandscapeSplineActors 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, 2016I 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 ...
Using a Macro to access a variable from another Actor causes a crash in Standalone
UE - Gameplay - Blueprint - Jun 8, 2015Using 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, ...
Niagara Scalability Crash When Processing Significance
UE - Niagara - Jun 4, 2025Method FNiagaraScalabilityManager::ProcessSignificance() iterates on indices from Context.SignificanceIndices and uses them to access the State and ManagedComponents arrays. It can then decide to cr ...