Can't create/open document

It happened yesterday while I was editing a picture. Suddenly, I wasn't able to create a new file or open one. Saving my file also didnt work. Opening a file only worked when i dragged it directly into PS.

Now, one day later, Photoshop opens up without the new Screen, where you can see all of your previously editet files etc. 

I am only able to create a new file if i go to preferences and select the old "new document" interface.

I tried restarting, reinstalling, resetting all settings and even reinstalling the Creative Cloud, nothing works for me.

Thank you in advance.