VR Packaged Game Crashing: Niagara Shader Module Delegate Never Set

After packaging my VR game and opening it, it instantly crashes with this error:

 Assertion failed: OnRequestDefaultDataInterface.IsBound() [File:D:/Build/++UE4+Licensee/Sync/Engine/Plugins/FX/Niagara/Source/NiagaraShader/Private/NiagaraShaderModule.cpp] [Line: 55]
Can not invoke OnRequestDefaultDataInterface. Delegate was never set.

My game works perfectly fine in the editor with niagara effects in game. I recently upgraded from 4.23 to 4.25 Preview. Does anyone know where I can find some information regarding this?

I have this exact same error, (non-VR) and the issue only occurs when I have Niagara system objects referenced by my actors or data tables. I can spawn niagara systems in Level Blueprints, place them in levels, but put any non-trivial Niagara system as a reference to spawn an emitter and BAM crash on packaged game.

This issue isn’t present on non-packaged builds. I’m on 4.24.3 and this is really painful. I run a source-build of the engine and I’m open to modifying the code just need a hint as to why this error is happening!

Apparently if I make the emitter’s CPUSim instead of GPUComp Sim there isn’t an error when running a packaged version. Unfortunately this doesn’t happen in a simple template project so it seems unlikely anyone will be able to investigate this.

Thanks for your response. That was indeed the fix for me as well. Seems very strange that CPUsim fixes it though.

We are also having this problem here on 4.24.1 - We have set all effects being referenced to be CPU sim although not ideal for performance and have set fixed bounds to true. We have made sure Niagara is correctly added to the Build.cs Module Dependencies but alas still have this crash on launch of built version of the game. This is getting really costly in terms of our developement time and is stopping us from progressing on the PFX front. Any help past what has been mentioned above would be amazing! I’ve posted an image of our crash even though its identical to the one above.


Same error here, 4.25.4 :frowning: But CPUsim Fix worked.

Still happening in 4.26.1 !

also in UE5 early access too!