When using Perforce, saving a level over another leaves the target umap file as "marked for delete"

UE - Editor - Workflow Systems - Mar 11, 2025

When working on a level asset and using command "File – Save Current Level As..." to save it over a different level asset, the engine first deletes the target level (that's going to be overwritten) ...

Crash Occurring in FD3D11DynamicRHIModule::FindAdapter()

UE - Graphics Features - Jul 13, 2016

Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 804] Array index out of bounds: 1 from an array of size 1 Source Context: 352 353 // We a ...

UE4Editor_SlateCore!TSharedFromThis<SWidget,0>::AsShared() sharedpointer.h:1221

Tools - Apr 18, 2017

This bug report was entered as new crash groups appeared linking to [Link Removed] which was marked as fixed for 4.15.1 and the previous reproduction did not reproduce the issue Error message: Ass ...

DataTable asset view runs out of (video) memory

UE - Editor - UI Systems - Slate - Feb 26, 2024

In some situation, Slate tries to secure incredible amount size data and run out of memory. This happens a cell having very long and complex serialized text appears on the editor and it is placed to ...

Conflict between sequencer transform track and Parent Constraint from the Animation Mode breaks temporary pivot translation on any actor

UE - Anim - Anim in Engine - Jul 15, 2025

Note: This affects all versions from at least UE 5.3, including mainline latest. The "Animation" Editor Mode allows creating constraints for level actors. One of these, the "Parent" constraint, con ...

Crash when manipulating Bone Space IK before setting EffectorSpaceBoneName

UE - Anim - Rigging - Feb 9, 2017

Error message: Assertion failed: Pose.IsValidIndex(BoneIndex) [Link Removed] [Line: 528] Source Context: 513 const FTransform& ParentTransform = GetComponentSpaceTransform(ParentIndex); ...

Translucent materials in the PostMotionBlur pass can cause a flickering viewport artefact when using TAA

UE - Graphics Features - Feb 5, 2025

There appears to be a bug relating to rendering multiple windows that can trigger under unknown circumstances. It has been reported on rectangle lights in the forums and on PostMotionBlur materials ...

Crash rendering image sequence if the Sub-Level with matinee is not loaded

Tools - Apr 15, 2016

Crash rendering image sequence if the Sub-Level containing the matinee is not loaded. This seems to go away if the level is either set to "Always Loaded". Seems to be a result of people not switch ...

Crash when Previewing specific LODs within Static Mesh Editor at certain Screen Resolutions

Tools - Oct 27, 2016

A crash occurs when attempting to preview specific LODs when the monitor resolution forces the menu to be expanded when selecting an LOD. This Jira was created from CrashReports submitted by the pu ...

Crash Importing Skeletal Mesh LODs with a lot of morph targets

OLD - Anim - May 18, 2016

Crash Importing Skeletal Mesh LODs with a lot of morph targets Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 785] Array index out of bounds: 2 from an ar ...