UE4 crashes if I add anything

I have tried both 4.17.2 and 4.16.3. Both the editors crashes whenever i add things like atmospheric fog. Directional light. Even player start. Please help!

See the crash report. Also go to Epic launcher and click on the verify option of that version of the engine

Thanks for the help. But my editor stopped crashing on its own for the time being. Lets see what happens.