Unreal Engine Issues
Unreal Engine Issues
A project on Mac that includes a static library will continue to use the old cached version of the library after the library is updated.
UE - Foundation - Cpp Tools - UnrealBuildTool - Sep 9, 2016If a static library that is included with a UE4 project is changed, the new version of the library is not used when the project is built again. Instead, the original cached version of the library is ...
Editor will crash while instancing nested AIPerception component template subobjects in an AIController-based Blueprint class during compile-on-load.
UE - Gameplay - Blueprint - Mar 23, 2018User report of an assertion that fires on editor reload during an attempt to reload an AIController-based Blueprint class with a dependency on a child Blueprint class, both created in a previous edi ...
Crash when changing parent of Material Instance with Layered Materials and viewing Layer Parameters
UE - Rendering - Architecture - Materials - Aug 1, 2025Reparenting a MaterialInstance that uses Material Layers to another instance with a different layer configuration can cause the editor to crash when opening the Layer Parameters tab. This appears to ...
UDN 472564 - CurlHttp merges headers on redirect
UE - Online - Dec 7, 2018when curl requests are redirected (301) – response headers are merged together and are comma separated. but, Content-Type headers are required to use semi-colon ";" separators. ...
UBT compiler output is garbled when run via UAT (Japanese system locale)
UE - Core - Cpp Tools - Oct 2, 2026When UnrealBuildTool (UBT) is launched by UAT, for example by RunUAT.bat BuildCookRun build, localized (Japanese) MSVC error messages show up garbled in the console and in UAT's Log.txt. The UBT log ...
Classes in TargetDenyList modules are still referenced from Components on BlueprintGeneratedClasses and cause runtime warnings
UE - Core - Systems - Feb 25, 2024Other than the presence of the error and the performance cost of looking for a package on disk that does not exist, there are no behavioral problems. When running with legacy (non-iostore) pakfiles ...
Copied references to Texture2D assets are not formatted correctly when the .csv containing those references is made into a Data Table asset in the Engine.
Tools - Feb 26, 2015Importing a .csv file that contains references to assets in the project requires the user to copy the references for each asset again before they will work correctly. The references do not need to b ...
If a child blueprint class has an Instanced/EditInlineNew object property, that property will always be detected as changed by the property editor (i.e. it will show a "Revert" arrow on that property), even if its properties are identical to the parent.
UE - Framework - Blueprint Editor - Dec 17, 2025Context: Blueprint classes can use Instanced/EditInlineNew object property specifiers to create and edit subobjects directly in the editor. Problem: If a child blueprint class has an Instanced/Edit ...
SelectActorsUsingThisAsset doesn't select actors that are referenced by an array and using a Scene component as root
Tools - Sep 11, 2015SelectActorsUsingThisAsset doesn't select actors that are referenced by an array and using a Scene component as root User Description: I have a BP with editable actor references array. Recently I ...
Crash when opening a project with Renderdoc plugin enabled while renderdoc is installed on the machine
UE - Graphics Features - Oct 6, 2020-The editor will crash when opening a project with the Renderdoc Plugin enabled while the user has Renderdoc installed on their machine. Uninstalling Renderdoc allows the project to open without cra ...