UE4 Crashes When Building Lights

So I’m a beginner in Unreal Engine and every time i try to build an environment, then build the lights, the program doesn’t respond, and I once waited for a while it but it was still not responding, I waited for like an hour and I didn’t even add any lights except the directional lights. What exactly happens is when it is exporting lighting data it suddenly does not respond. This disappoints me whenever I try to create something because this wastes my effort and wastes everything I created. If anyone can help me I would really appreciate it. My processor is Intel(R) Core™ i7-4770 CPU @ 3.40 GHz 3.40 GHz. And the RAM is 12.0 GB.


the engine crashes? the light never finishies building? What happens exactly?

Well you know this (Program) is not respond pop up thats what happens when I press bake.

I mean build

What type of lights are you using static, stationary or moveable? How many lights do you have roughly? High or low volume. Also if most lights are set to moveable this will cause dynamic lighting that takes the longest to render.

actually static light meshes are the longest to build, so try to set all meshes to movable, and try to build, so we can see if changes the problem

Haha sorry I meant static :S But like Filipe says - change them all to moveable and build again - maybe even delete certain lights that aren’t fully necessary.

Well as I said its not the problem with lights because I said I used only a directional light. And in all the courses when someone presses build it takes 5 seconds to build the same light that I used.

I think it crashes when it is exporting lighting data and I found out it doesn’t have to be 50%.

And Yes I changed all meshes to moveable and this doesn’t fix anything…

well, when you build the project, it builds the lights, so, changing the meshes to movable will change the way the engine process it, if you build and it reaches 50% and stops, could be the static light of a specific mesh that is glitched. You need to test all kind of things until find what is causing the problem

when you build the lightmass consumes a lot of memory ram?

how do I know?

open your task manager of the windows when you build the project, it will show the memory usage, if it is using too much, you may have to increase the virtual memory of your computer

How much is “too much”?

I opened a default template and clicked build and the memory usage was about 3.8 or less GB

I have 8GB memory RAM and I already had a problema like that, when I build it was consuming almost all the 8GB memory, was very crazy.

So I increased the virtual memory of my PC a LOT, I have a total of 90GB of virtual memory. Never had this kind of problem anymore!

yes, it is too much right? a default template consuming almost 4gb, it is a lot. It was happening to me too.

Increase your virtual memory, here is a way to do that: ✔️ Windows 10 - Optimize Performance - Virtual Memory - Advanced System Settings - Speed Up Win 10 - YouTube

I have the same issue… everytime i try to build any project… UE crashes…
even though my RAM usages is under 60% usage… any help would be appreciated

I have the same problem.

Even I try to rebuild light only in starting default scene (even 1 cube and direction light), every time UE 4 in frize, not respond. My memory 12Gb and virtual memory 36Gb.
Already tryed to change video drivers - no result.