Unreal Engine Issues
Unreal Engine Issues
AnimNotify serialization crash in editor
UE - Runtime - Animation - Mar 15, 2026The crash is caused by changing the variable type of an AnimNotify that is already referenced by a montage. This issue cannot be reproduced in 5.6. ...
MotionWarping does not recognize new MontageInstance with the same montage
UE - Characters - Animation - Jan 11, 2023When the same AnimMonotage is played again while moving with MotionWarping & RootMotion, UAnimNotifyState_MotionWarping does not recognize it. From licensee: The issue was that in URootMotionMod ...
[CrashReport] Access violation - FLandscapeEditDataInterface::SetAlphaData()
UE - LD & Modeling - Terrain - Landscape - Jul 19, 2017This is a common crash affecting users in 4.15 and 4.16. This callstack was previously linked to [Link Removed], but that had a specific repro case that was fixed in 4.14. Users are not providing ...
Assigning a static mesh to a Mutable Clip Mesh With Mesh Node can crash the editor
UE - Anim - Mutable - Jul 4, 2025Context: The Mutable plugin has a modifier node called Clip Mesh With Mesh that allows Static Mesh modifiers to be assigned as the clip mesh. Under certain circumstances, an assert can be triggered ...
Crash when quick binding a function in a class that extends LevelSequenceDirector
UE - Anim - Sequencer - Sep 16, 2020The purpose was to create a Level Sequence Director inheritance class so that the same event could be reused in multiple sequencers. Attempting to quick-bind this base Level Sequence Director event ...
Issue with importing alembic files: the skeletal mesh asset doesn't contain LOD description
UE - Editor - Open File Formats - Sep 15, 2026Helloo everyone!! 😄 We are experiencing an issue with importing skeletal meshes from alembic. For reference, this issue happens in vanilla engine 5.7.4, but it doesn't occur in versions 5.6.x. 1) ...
If using SetAlignmentInViewport in Construct, the value with it is ignored
UE - AI Workflows - UI Systems - UMG - Jan 27, 2023If SetAlignmentInViewport is called in the UMG Construct, it is ignored internally. This is due to a change that came in 5.1, so it worked fine in 5.0. First, when the Set Alignment in Viewport nod ...
Open Formats: Interchange Import Runtime - Interchange ImportAssetAsync runtime GLB import — materials, textures, tangents, and shaders non-functional in packaged builds (6 issues, UE 5.7.4)
UE - Editor - Open File Formats - Apr 30, 2026Description* We are using Interchange's `UInterchangeManager::ImportAssetAsync()` to import GLB files at runtime in a packaged (Shipping) application. The orchestration layer (`ImportInternal` in `In ...
SpringArmComponent with "Use Camera Lag Substepping" does not handle fluctuating frame rates correctly
UE - Gameplay - Jun 4, 2024The description of SpringArmComponent's "Use Camera Lag Substepping" option says "sub-step camera damping so that it handles fluctuating frame rates well". However, as noted and explained by a licen ...
[CrashReport] UE4Editor_Core!FText::FText() [text.cpp:165]
Tools - Jan 12, 2017This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Access violation - code c0000005 ( ...