UE5 Crashes When Opening Level (Urgent!)

I’m doing a set dressing test for a possible job and I thought I’d use UE5, which probably wasnt the best idea in the first place, but I have added some Epic marketplace content (Rural Australia Pack, Ancient Treasures, and City of Brass )to the Valley of the Ancient project and created a custom level. All was fine for the last week, then trying to wrap up the level and I got a crash. Went to reopen and on the splash screen it gets to %100 and goes to open the editor and the Crash Report comes up, everytime with this message

“Assertion failed: BatchElement.IndirectArgsBuffer [File:D:/build/++UE5/Sync/Engine/Source/Runtime/Renderer/Private/MeshPassProcessor.cpp] [Line: 786] It is only valid to set BatchElement.NumPrimitives == 0 when a IndirectArgsBuffer is used.”

I’m absolutely gutted, need to take screenshots asap and submit them, but I’m an artist and not super technical so not sure what to try or where to even look. I pulled up visual studio to the line of code its referencing, but not sure what to do? I have a log but cant upload as I have a new account.


Stick a breakpoint on line 786

When it is hit, look at the structure MeshBatch and see if you can tell what asset it is trying to load

You may then be able to delete that asset , or use the command line to cook the assets before you open the editor

I have the exact same error. The only difference is that mine will randomly pop up in a specific enviroment.

@RianS , not a solution to your crash but I would suggest changing the default start map. You can do this in the config files, or more crudely simply rename/move around the defaultmap. (I am assuming here that your defaultmap is the map you are working on).

This will let you load the project so you can change/remove things that are faulty.

@PaulBlythe
yeah… about the breakpoint… could you explain how to set this up?

Has anybody found a fix for this issue yet?

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