Everytime I open Unreal, it gets to 95% and it crashes. Doesnt even open. I dont understand what the problem could be. Previously I changed my lightmaps to 2048 on two big pieces of terrain and enabled LOD settings. Afterwards, this kept happening. Any reason why? I have a lot of space in my internal drives.
Revert the change and test. How big is big? Over 6Km you will have issues.
Space on internal drive has nothing to do with the out of memory crash - for that you will need more RAM. I have 64GB of RAM.