Editor Crashing on Bake Material of Skeletal Mesh

Hi Epic team,
I was just exploring the bake material feature, then I encountered a crash while baking material from skeletal mesh of paragon hero.

Steps to reproduce

  1. Open Narbhash hero skeletal mesh.

  2. Click on bake material and let the default settings be as it is and confirm.

  3. Wait for few seconds, editor will crash.

Below I m attaching the screenshot from my PC.


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I have submitted the bug report for UE 4.20, then one the Epic engineer replied to me stating its been already fixed in UE 4.21.
But in 4.21 also its crashing because of Array Index Out of bound exception. This is not acceptable, after fixing one thing its causing another crash.
I also work in a product based company, if you have your product then make it bug free, everywhere UE crashes.
I can also fix those bugs and crashes but I don’t have enough time to dedicate for bug and crash fixing.

Its really annoying, take my advice and please iterate UE 4.22 only for bug fixing, no feature addons only bug and crash fixing.

This I have solved all by myself, the epic guys totally refused to solve this issue as it was only happening on my end as they stated. At least they should have given some tips to solve, but no they are indeed thick-skinned, arrogant and annoying.

So, how did you solve it? I am having the same issue.

I have just commented the line 414 in file MeshMergeUtilities.cpp and built the solution.

This is the line which is commented.
const FSectionInfo& SectionInfo = UniqueSections[Pair.Key];

I don’t know what it does.

You can check that line 414 in that file.

I was using the source version of UE4.

I am getting different crash:

Assertion failed: (Index >= 0) & (Index < ArrayNum) [File:D:\Build++UE4\Sync\Engine\Source\Runtime\Core\Public\Containers/Array.h] [Line: 614] Array index out of bounds: 3 from an array of size 3

If you see it properly, it is because of array out of bounds exception for TArray class.
So MeshMergeUtilities.cpp is the source where it is trying to access elements out of bounds of limit.
So if you comment out that line and recompile the engine it will work fine.

HI. I have had trouble recently exporting ‘MetaHumans’ with good materials in 3ds Max,.

I found that if I COPY the skeletal mesh, then convert the copy to a static mesh (just for baking purposes) I am finally able to bake! (EXCITING!!!)

ALSO it can fail out, IF YOU DO NOT HAVE ENOUGH HARD DRIVE SPACE, on the drive UE4 is installed onto.

:slight_smile: If you have any interest, come see my upcoming show ‘WORKING (while) IN VR!’ at: youtube.com/NextWorldVR

Subscribe for premiere announcement. :slight_smile: -Woody