VS Code undable to open files

I use VS Code as my code editor. Today while I was working on a React app I was suddenly unable to open any files. My technical skill with VS Code is lacking so I have no idea what might have caused this.

This is the error I get: Unable to open ‘index.js’: Assertion Failed: argument is undefined or null.

It throws this error for every single file I try to open. If anyone might have some suggestions on what I can do to fix the problem I would be extremely grateful. I’m downloading Atom at the moment but I’d rather stick to VS Code for now as that’s what I’m used to. Thanks in advance.