This is nuclear, but effective for persistent Error 150. This disables a Windows audio protection feature that sometimes blocks legacy games.
Warning: Back up your registry first (File > Export).
Corrupted Realtek drivers are a prime suspect for Error 150.
To do a clean install:
The MSS system is old. Forcing Windows 8 compatibility often resolves API conflicts.
ERR MSS INIT FAILED 150 points to a problem with Microsoft DirectX or the game’s ability to initialize the Multi-Threaded Software Sound (MSS) system. It often appears on launch or when switching graphics settings.
Common causes:
Windows Defender or third-party antivirus (looking at you, McAfee and Norton) has a nasty habit of quarantining the mss32.dll file. Why? Because MSS hooks deeply into your system's audio threads. To a heuristic scanner, that looks like a rootkit. The anti-virus doesn't kill the game; it just steals the voice box.
You don’t need to reinstall Windows. You don’t need to buy a new GPU. Here is the actual fix.
Step 1: The Sample Rate Surrender
Step 2: The DLL Resurrection
Step 3: The Arithmetic of Audio
To understand Error 150, you must first understand MSS ( Miles Sound System ). Before the era of proprietary audio engines, a company called RAD Game Tools created a middleware solution that allowed games like Call of Duty to manage 3D positional audio, Doppler effects, and voice chat without forcing developers to reinvent the wheel every time. Call of duty exe err mss init failed 150
MSS is the puppet master. It tells your gun where to echo, your footsteps where to crunch, and Captain Price where to growl. Error 150 is the moment the puppet strings snap.