The error in Call of Duty: Black Ops 2 is a common initialization crash caused by missing, corrupted, or mismatched language asset files in the game's installation directory . This issue typically triggers during startup across Single Player, Multiplayer, or Zombies modes when the engine looks for essential English audio/font archives ( cmn_root ) and finds them incomplete or entirely absent.
The error code, sound bank failed to load cmn-root.english , essentially means the game engine cannot find or access a critical audio file it needs to run. "Sound banks" are packaged audio files, and "cmn-root" is a core folder, so the game is being told that a fundamental audio component for the English language version is missing. The error in Call of Duty: Black Ops
*Default path: C:\Program Files (x86)\Steam\steamapps\common\Call of Duty Black Ops II* Open the folder. Open the DirectX folder inside it. Find the file named DXSETUP.exe . Right-click DXSETUP.exe and select Run as Administrator . "Sound banks" are packaged audio files, and "cmn-root"