In case you have installed a new operating system, sometimes Steam may not recognize your game files. Here’s a solution.

  1. Run Steam, then click on Steam and select Settings.
  2. Select the Downloads option.
  3. Click on the Downloads tab, then click on Steam Library Folders. The program will then open a new window.
  4. Add your old game library. In the pop-up window, click on Add Library Folder and select the location where you save all your Steam game data that you have transferred, for example, from the old operating system.
  5. Select the file. Click on Select and close Steam settings. Then exit the Steam application and restart Steam. Steam should now recognize the installed games again and display them in the game folder.

Note: By default, Steam stores game data in the Steamapps folder in the designated installation location. Therefore, if you have a dedicated location where your game data is stored, you can try adding the location in the Steam application to fix this issue.