How to enable denoising for my final render? I have been fiddling around with the LuxCoreRender rendering settings, but both denoisers do not seem to be having effect on my frames that I have rendered. 

I have re-installed LuxCoreRender multiple times, and used the default settings + my own custom settings to try to get it to work, but for some reason it will not. The viewport denoiser is working perfectly, however. Also, if I set the denoiser settings to be heavier on denoising, Blender will quit, running out of memory.

Q: Is there some way I can use the same settings for the viewport rendered view, and somehow apply them to the rendered frame settings?
Make sure the dropdown on the top right of the Image Viewer is set to the correct pass (DENOISED):



I'd suggest render to OpenEXR Multilayer to get both passes (beauty and denoised) in one file for comp:



Alternatively you can add a Render Layer node in the Compositor to get the DENOISED socket and connect both passes to a File Output node or even blend between both passes before saving:



Note: The Composite Node has only one input socket so this approach does not store any raw data.