Unreal Engine Issues
Unreal Engine Issues
Assertion failed: (Index >= 0) & (Index < ArrayNum) when importing large Alembic file
UE - Editor - Content Pipeline - Datasmith - Importer - May 3, 2022Regression testing done on //UE4/Release-4.27.2 CL-18427296 and this issue did occur. [Link Removed] [Link Removed] Below is snips of customers description and proposed workaround:Importing alembi ...
Children of editor-only actors do not maintain correct transforms when placed inside level instances for PIE and cooked builds
UE - World Creation - Worldbuilding Tools - Level Instances - Oct 20, 2025We have found an issue where children of editor-only actors get wrong transforms in PIE and cooked builds when placed inside level instances. This affects both engine version 5.5 and 5.6. The issue ...
Crash when trimming animation and then undoing action
UE - Anim - Runtime - May 30, 2023Repro rate: 3/3 times This is a regression as the issue does not occur in 5.1.1 ...
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 ...
FBX: Camera imports to Matinee with skewed position and rotation
UE - Editor - Content Pipeline - Import and Export - Aug 27, 2013Branch Build Label Changelist UE4-Main UE4_[2013-08-27_14.24] 1799942 DESCRIPTION: When importing an animated camera from Maya into Matinee, the placement of the camera is changed (shifted 90 ...
NPC - Instances does not get updates from changes to the parent Niagara Parameter Collection in the editor
UE - Niagara - Oct 4, 2024When an Niagara Parameter Collection (NPC) is selected as the parent Collection for an NPC Instance (NPCI), all of its current parameters are carried over to the NPCI with their current values as th ...
Attempting to build lighting in project crashes editor
UE - LD & Modeling - Terrain - Landscape - May 18, 2016Attempting to build lighting in user's project crashes editor. Frequency: 3/3 CrashReporter: N/A ...
Crash when fast moving Character objects has Teleporting enabled
UE - Simulation - Physics - Character - Nov 28, 2022Reproduced 3/3 times. Issue does not occur in //UE4/Release-4.27, so Confirmed Regression. ...
Editor crashes when actors using child actor component are loaded while Static mesh actor filter is enabled in the outliner
UE - Editor - Dec 5, 2022Reproduced 3/3 times. Unclear whether this is a regression as filter GUI is new in 5.1 for Outliner. ...
Creating "Level Sequence with Shot" with spawnable cameras creates duplicate cameras
UE - Anim - Sequencer - May 31, 2023This is not a regression as it does occur in //UE5/Release-5.1 @ CL 23901901 Repro Rate: 3/3 times ...