Avoid using desktop icons, which often break. Instead, launch the game directly from your Steam Library .
The most common cause. You installed ATC4 on your D:\ drive, but you later moved the folder to C:\Users\Games\ . The shortcut still points to the old location. Windows searches D:\ATC4\ATC4.exe , finds nothing, and throws the error.
Avoid using desktop icons, which often break. Instead, launch the game directly from your Steam Library .
The most common cause. You installed ATC4 on your D:\ drive, but you later moved the folder to C:\Users\Games\ . The shortcut still points to the old location. Windows searches D:\ATC4\ATC4.exe , finds nothing, and throws the error.