Second way to fix the error is to download steam_api.dll from somewhere (there are plenty of those websites to download it, but I trust none of them), and then copy it to: To fix an error you should buy a game or disable antivirus, reinstall a program, and run it again. The most often reason for steam_api.dll is missing error is that you’ve downloaded a cracked game - in this case, the steam_api.dll file in a game is modified and your antivirus may have removed it from your computer (see the antivirus reports).