Crash upon attempting to compile a blueprint while Git source control is active

If a user connects to source control through the Git plugin and creates a repository, when they try to compile a blueprint, they can sometimes crash ...

Niagara - The "Apply" button on the toolbar does not get enabled when changing the checked state of an entry in "Propagated Static Switch Values" for a function call node.

UE - Niagara - Apr 7, 2025

Consider a Niagara Function Script containing a Static Switch node with the "Expose as Pin" option disabled for its selector variable. Now consider another Niagara Function Script or Module Script ...

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 ...

[Mobile/Forward Rendering] PlanarReflection does not work when the reflection plane faces certain directions

UE - Platform - Mobile - Sep 24, 2025

Note: This repros on 4.27 and all 5.x versions. When using the mobile renderer and/or forward shading, Planar Reflection will simply not work if the reflection plane normal has components that add ...

Auto-Save failing, pulling old saves and blocks users from continuing

UE - Editor - Workflow Systems - May 15, 2023

Reporting an issue where are users are getting prompted to auto-save, but then it appears to fail and asks them to manually save. They're being prompted with outdated save files, but get stuck in a ...

It is possible to rename a Function Output the same as a Local Variable, which causes a compile error

UE - Gameplay - Blueprint - Apr 15, 2015

It is possible to rename a Function Output the same as a Local Variable, which causes a compile error: Error Internal Compiler Error: Tried to create a property TestVar in scope NewFunction_0, but ...

If using SetAlignmentInViewport in Construct, the value with it is ignored

UE - Editor - UI Systems - UMG - Jan 27, 2023

If 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 ...

Hardware Lumen Surface Cache Artifacts on Nanite Geometry

UE - Graphics Features - Lumen - Sep 1, 2025

When using Hardware Lumen with Nanite-enabled meshes in UE 5.6+, black / dark surface cache artifacts appear that result in generally darker and unstable lighting. These artifacts are not immediatel ...

[CrashReport] UE4Editor_D3D11RHI!TerminateOnDeviceRemoved() [d3d11util.cpp:176]

UE - Graphics Features - Nov 18, 2016

Error message: Fatal error: [Link Removed] [Line: 176] Unreal Engine is exiting due to D3D device being lost. (Error: 0x887A0006 - 'HUNG') Source Context: 161 162 const TCHAR* Rea ...

Deleting elements from TMap Struct in actor blueprint editor causes Crash

UE - Editor - UI Systems - Slate - May 24, 2019

Deleting elements from TMap Struct in the Actor Blueprint Editor (specifically, deleting elements from them) causes Unreal to crash ...