Epic Games Launcher empty

Hi,

I have a big problem and thank you for your help in advance.

My Epic-Games-Launcher is empty as show in the pic. Tried a lot after studying the web and this forum, but nothing helps. Any ideas? I think it won’t help to count all the different changes I made yet. I would like to install Fortnite, but how if I don’t see it in the launcher?

Thank You!