Unreal Engine 4.11.2 crashes at start

I installed UE 4.11.2, created my first test project, all works fine. Then I renamed folder and project file and UE starts to crash trying to open it. Ok, I completely remove project folder. Now UE always crashes at start. I thought to migrate to UE from Unity but after 10 minutes I cannot run UE at all. This is awful. How can I fix this issue?

It started to work after a reboot.