Greetings @JohnGiotto
Welcome to the Unreal Engine Community Forum. The information and link Leo provided is definitely a good place to start. I’d also recommend checking out === Critical error: === Failed to compile default material /Engine/EngineMaterials/WorldGridMaterial.WorldGridMaterial! if you’re unable to resolve it from Leo’s link. There a few things to try on there that users have had success with as well. Let me know if after both suggestions you’re still running into the problem. Thanks!