Why is the Epic Games launcher not detecting installed or downloaded games
One reason might be that you reset or reinstalled Windows.
If your games are saved on another drive but the Epic Games launcher is on the same drive as Windows, resetting or reinstalling Windows can delete system settings and the launcher. It also removes the registry entries that help the launcher remember your installed games. When you reinstall the launcher, it won’t know the games were already installed.
Or sometimes, something on your computer changes, and the launcher suddenly stops detecting your games for whatever reason.
How to make Epic Games launcher detect existing or downloaded games
First, make sure to move your existing game folder to a different location. If your games are usually installed in D:\Epic Games, do not keep the existing game folder there. Instead, create a new folder, like D:\Epic Games\Backup, and move the existing game folder into that folder.
Lets say the game is Fall Guys (originally installed in D:\Epic Games\FallGuys). Here is how your folders should look like after moving:
D:\Epic Games ← Fall Guys folder has been moved
D:\Epic Games\backup\FallGuys ← this is your existing game that you moved
Now, go to Epic Games launcher and start downloading the game (Fall Guys). Once the download begins, cancel it. This will create the game folder. You will now have a folder at D:\Epic Games\FallGuys.
Now your folders should look like this:
D:\Epic Games\FallGuys ← launcher created the new Fall Guys folder
D:\Epic Games\backup\FallGuys ← this is your existing game
Open D:\Epic Games\FallGuys (not your backup folder) and delete everything in it. This folder is not your existing game.
Open your existing game folder (D:\Epic Games\backup\FallGuys) and move everything into D:\Epic Games\FallGuys.
Your folders should look like this:
D:\Epic Games\FallGuys\FallGuys ← WRONG, because you moved the folder not its content
D:\Epic Games\FallGuys ← CORRECT
D:\Epic Games\backup\FallGuys (now empty/moved)
Final step is to go back to Epic Games launcher and click Fall Guys. It will now start verifying the game instead of downloading.
Tutorial video: