I can't launch Unreal Engine

As the title said, I found out that I can’t launch Unreal Engine 4. When it comes to click launch UE4 the yellow button says ‘busy’ the ‘pls wait’, so I wait for it for about 5 seconds then it says ‘launch’ again, like this every times. I’ve already clicked ‘verify’ and downloaded debug but those doesn’t help.So I thought it may be about my computer,but My computer is intel i5 with Nvidia 6000 series graphic card, so I don’t think its about that. Besides I already checked out, that I downloaded it correctly. I don’t know now what to do next. Please help

I have the same problem, i don’t know ho to help though.