Navigate to your Steam installation folder.Click the Steam option at the top left part of the Steam client and choose Exit in order to exit Steam completely (don’t just click the x button at the top right corner).Make sure you pause the download by hovering over the Library tab at the top of the window and clicking Downloads.
The game should be listed as not installed and the download process should start. Right-click on its entry and choose Play Game.Head over to the Library tab in the Steam window by locating the Library tab at the top of the window, and locate the problematic game in the list of games you own in your library. Start Steam by double-clicking its icon on the Desktop or by searching for it in the Start menu.Moving these files out and back in should help resolve the problem as it did for many other users who followed the same guide on Steam forums. There are certain files inside your game’s installation folders which manage the games which are currently installed. Steam library folders are not set up – If you have recently reinstalled Steam, you will have to add the Steam library folders you have used again if you want Steam to find the games you have installed there.Also, if Steam is unable to access this file because of permissions issues, the problem is bound to appear. If these files are broken or missing, the game will appear as uninstalled. ‘.acf’ files are faulty, missing, or inaccessible – These files are responsible to hold data regarding the current state of the game and they also show info regarding game files.