Unreal Engine dont start! And crashes!

I use the version 4.17.2 for my newest project. Since the last crash it wont start! The launcher stucks at 45%, but if I start the project twice the second one is working. When I do something like saving the project or building light it is crashing again! How can I fix this?

Tell me please, if you have a solution for that!

I have the same issue. The editor just crashes if I add anything.

You can try to verify the files of the UE4 by clicking on the arrow button and click verify. Not sure if it works. My UE4 crashed a few times but then somehow it started working properly again. Dont know how.