Unreal Engine 4 Crashed When Loading Project

Everytime I opened my project and Unreal Engine 4 all my works are unaccessible,please help me!!! !!!

create a new blank project and try to copy all ur assts in its directory! I downloaded a sample project from internet and when ever i try to open it! it crashes! so i just copied its contents to a blank project and it worked! hope it works for too.

I did and when I was loading my level in new project it crashed again ,anyway thanks for your reply.