4.26 won't launch because of ShaderCompileWorker.exe

Hey guys, I have been stuck on this issue for a long time, across a few versions.

Basically, when I open a scene or create a scene from the default template, the splash screen will get stuck at 39% forever, while 8 or 9 ShaderCompileWorker.exe instances take all 100% of CPU resource, until I end the UE4editor.exe process when my patience runs out. So I won’t even get to see the UE4 interface at all.

I did lots of comparisons and boiled down to a theory. When a default scene was created and could be opened properly, if I go to the project settings and enable DirectX 12 and raytracing, the system will ask me to restart. When I restart, this same scene that could be opened a few minutes ago, will now also freeze at 39% and won’t even let me get to see the interface.

Some other templates also can’t load, like the car template under Automobile/Product Design.

So, I have a laptop with 1 integrated Intel GPU and 1 RTX 2060 GPU. In order not to confuse UE4, I set all the programs to use my RTX 2060.

I also tried the tricks provided by other people here, including lowering the priority of the compile worker to low, and change the in file to make the compile happen after the editor is fully loaded. None of these 2 approaches work for me.

My video card driver has been updated to the latest version. Any help please?

Thanks a lot!


I have the same problem right now… Did you find a fix?


This recently happened to me , i think it was because i switched to “vulcan” as the default RHI render in project settings . Then When i opened the project in explorer and went to “config” folder and game engine settings and removed " vulcan" just left " default graphics " in there , then it would open again. Not sure , but i think so.