UEFN crash on startup assertion failed.

Ok I tried everything and just for fun decided to run UE5 and UEFN in windows 8 compatibility mode, with rivatuner closed, updated driver it finally worked. I fixed it with the windows program troubleshooter I selected the app and it suggested running it in windows 8 compat mode and it worked. There must be some call made to the gpu that makes it crash, probably related to rtx or dx12 or both because now it works like a charm!

Edit: Step to ensure you don’t crash.
1: windows 8 compatibility mode
2: reinstall drivers completely with a clean wipe (use DDU) (just to be on the safe side)
3:make sure to close rivatuner (you can also close afterburner)

Optionial: add TdrLevel into registry files a quick google search will help you with this, but I don’t advise to play into registry files if you are not familiar with it.

The unreal engine makes call to the gpu which are not fully compatible with windows 11, probably relating to shaders/rtx/dx12, which is why it is working with an older class gpu (1070ti here) I hope this helps other find their way into UEFN.

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