World Partition - Deleted actors can become unloaded prior to saving

UE - World Creation - Worldbuilding Tools - World Partition - Apr 11, 2025

In world partition levels, deleted actors can become unexpectedly unloaded prior to saving, causing loss of work. Specifically, this issue occurs after the undo history has been cleared (either manu ...

[AI] Navmesh does not generate correctly on a plane that has a slope of 45 degrees or more.

UE - AI - Navigation - Sep 23, 2022

Navmesh generation appears to have issues handling terrain and planes that are at 45 degree or steeper angles even if the agent max slope is set to allow for such movement. While the issue occurs at ...

[CrashReport] <unknown module>!UE4Editor_Core!FDebug::AssertFailed()

UE - Foundation - Core - Mar 28, 2016

Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 678] Array index out of bounds: 0 from an array of size 0 Source Context: 80 } 81 else ...

Typo in "BaseEditorSettings.ini": under section [/Script/UnrealEd.ContentBrowserSettings], key "DisplayPluginFolder" (singular) should read "DisplayPluginFolders" (plural).

UE - Editor - Workflow Systems - Oct 11, 2025

File "<ENGINE_PATH>/Engine/Config/BaseEditorSettings.ini" contains the following setting: [/Script/UnrealEd.ContentBrowserSettings] ; Whether to display the game project plugins in the Content Brow ...

[CrashReport] Crash Occurs When Deleting All Content From a First Person Project

Tools - Aug 23, 2016

Error message: Access violation - code c0000005 (first/second chance not available) Source Context: 103 /***********************/ 104 /******** Outer ********/ 105 /****** ...

Crash when resizing window using Quad Stereo Buffer

UE - Virtual Production - nDisplay - Oct 2, 2019

We noticed crashes in our application when we attempted to resize a window or switch to full-screen mode. Hence, resizing windows and switching to full screen will result in a crash on Unreal Engine ...

Crash Importing some assets with "Keep Overlapping Vertex"

UE - Editor - Content Pipeline - Import and Export - Nov 29, 2016

Download offending asset here: [Link Removed] Error message: Assertion failed: NewPosition >= 0 [Link Removed] [Line: 452] Source Context: 438 virtual ~FFileHandleWindows() 439 ...

Editor Crashes When Updating Captures on Sphere Reflection Captures

UE - Graphics Features - Feb 20, 2017

Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 633] Array index out of bounds: -1 from an array of size 11 Source Context: 200 CubemapArray.Updat ...

UE4 Crashes if multiple Vive Trackers or Lighthouses are used

UE - Platform - XR - Jan 24, 2018

User reports that if more than 5 trackers are connected, UE4 crashes Suggested fix: Root cause of bug is related to the fact that UE has no setup to receive input events from Vive Trackers. (we ha ...

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 ...