Project won't load even after known working backup copied over

My project will no longer load. It says it has the problem with the game module.
I guess there are files outside the project folder that Unreal relates to? I copied all the files from the working backup over it. Does that not suppose to be enough?

First try this: don’t copy the backup on top of the other one, give it a new directory and build from scratch. That usually works. You can even try your latest version (if it should be working as well) this way. Easiest way is to package a zip and then unzip it into a new directory.

If that doesn’t work then try removing (completely) and reinstalling UE4.

What you don’t want is for all those intermediate directories to be reusing generated stuff instead of rebuilding them. This is especially true for overwriting versions but can also happen between builds of the same version sometimes (no rhyme or reason). Just changing a line of code has caused my project to go kaput. Somehow it propagates into the blueprints and then all hope is lost.

In the meantime you could post the logs just in case there is a legit error.